diff --git a/samples/WinForm32/Form1.cs b/samples/WinForm32/Form1.cs
index 5deb905..bca04eb 100644
--- a/samples/WinForm32/Form1.cs
+++ b/samples/WinForm32/Form1.cs
@@ -20,7 +20,7 @@ namespace WinFormSample
     public Form1()
     {
       InitializeComponent();
-      var libVer = FileVersionInfo.GetVersionInfo(typeof(TwainAppSession).Assembly.Location).FileVersion;
+      var libVer = FileVersionInfo.GetVersionInfo(typeof(TwainAppSession).Assembly.Location).ProductVersion;
       Text += $"{(TwainPlatform.Is32bit ? " 32bit" : " 64bit")} on NTwain {libVer}";
 
       TwainPlatform.PreferLegacyDSM = false;
diff --git a/src/NTwain/Data/ValueWriter.cs b/src/NTwain/Data/ValueWriter.cs
index 345a061..8e4c358 100644
--- a/src/NTwain/Data/ValueWriter.cs
+++ b/src/NTwain/Data/ValueWriter.cs
@@ -8,7 +8,7 @@ namespace NTwain.Data
   /// <summary>
   /// Contains methods for writing vairous things to pointers.
   /// </summary>
-  static class ValueWriter
+  public static class ValueWriter
   {
     /// <summary>
     /// Allocates and copies the string value into a pointer in UTF8 that's null-terminated.
@@ -38,556 +38,605 @@ namespace NTwain.Data
 
     // most of these are modified from the original TWAIN.CsvToCapability()
 
-    //public static void WriteOneValueContainer<TValue>(IMemoryManager memMgr, ref TW_CAPABILITY twCap, TValue value) where TValue : struct
-    //{
-    //    IntPtr lockedPtr = IntPtr.Zero;
-    //    try
-    //    {
-    //        if (twCap.hContainer != IntPtr.Zero) memMgr.Free(ref twCap.hContainer);
+    /// <summary>
+    /// Creates a <see cref="TW_CAPABILITY"/> with a one-value container.
+    /// Caller will be responsible for ensuring memory is freed.
+    /// </summary>
+    /// <typeparam name="TValue"></typeparam>
+    /// <param name="cap"></param>
+    /// <param name="memMgr"></param>
+    /// <param name="value"></param>
+    /// <returns></returns>
+    public static TW_CAPABILITY CreateOneValueCap<TValue>(this CAP cap, IMemoryManager memMgr, TValue value) where TValue : struct
+    {
+      TW_CAPABILITY twCap = new() { Cap = cap, ConType = TWON.ONEVALUE };
 
-    //        TWTY itemType = GetItemType<TValue>();
+      IntPtr lockedPtr = IntPtr.Zero;
+      try
+      {
+        //if (twcap.hContainer != IntPtr.Zero) memMgr.Free(ref twcap.hContainer);
 
-    //        // Allocate the container (go for worst case, which is TW_STR255)...
-    //        if (TwainPlatform.IsMacOSX)
-    //        {
-    //            twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_ONEVALUE_MACOSX)) + Marshal.SizeOf(default(TW_STR255))));
-    //            lockedPtr = memMgr.Lock(twCap.hContainer);
+        TWTY itemType = GetItemType<TValue>();
 
-    //            TW_ONEVALUE_MACOSX twonevaluemacosx = default;
-    //            twonevaluemacosx.ItemType = (uint)itemType;
-    //            Marshal.StructureToPtr(twonevaluemacosx, lockedPtr, false);
+        // Allocate the container (go for worst case, which is TW_STR255)...
+        if (TwainPlatform.IsMacOSX)
+        {
+          twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_ONEVALUE_MACOSX)) + Marshal.SizeOf(default(TW_STR255))));
+          lockedPtr = memMgr.Lock(twCap.hContainer);
 
-    //            lockedPtr += Marshal.SizeOf(twonevaluemacosx);
-    //        }
-    //        else
-    //        {
-    //            twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_ONEVALUE)) + Marshal.SizeOf(default(TW_STR255))));
-    //            lockedPtr = memMgr.Lock(twCap.hContainer);
+          TW_ONEVALUE_MACOSX twonevaluemacosx = default;
+          twonevaluemacosx.ItemType = (uint)itemType;
+          Marshal.StructureToPtr(twonevaluemacosx, lockedPtr, false);
 
-    //            TW_ONEVALUE twonevalue = default;
-    //            twonevalue.ItemType = itemType;
-    //            Marshal.StructureToPtr(twonevalue, lockedPtr, false);
+          lockedPtr += Marshal.SizeOf(twonevaluemacosx);
+        }
+        else
+        {
+          twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_ONEVALUE)) + Marshal.SizeOf(default(TW_STR255))));
+          lockedPtr = memMgr.Lock(twCap.hContainer);
 
-    //            lockedPtr += Marshal.SizeOf(twonevalue);
-    //        }
+          TW_ONEVALUE twonevalue = default;
+          twonevalue.ItemType = itemType;
+          Marshal.StructureToPtr(twonevalue, lockedPtr, false);
 
-    //        WriteContainerData(lockedPtr, itemType, value, 0);
-    //    }
-    //    finally
-    //    {
-    //        if (lockedPtr != IntPtr.Zero) memMgr.Unlock(twCap.hContainer);
-    //    }
-    //}
+          lockedPtr += Marshal.SizeOf(twonevalue);
+        }
 
-    //public static void WriteArrayContainer<TValue>(IMemoryManager memMgr, ref TW_CAPABILITY twCap, TValue[] values) where TValue : struct
-    //{
-    //    IntPtr lockedPtr = IntPtr.Zero;
-    //    try
-    //    {
-    //        if (twCap.hContainer != IntPtr.Zero) memMgr.Free(ref twCap.hContainer);
+        WriteContainerData(lockedPtr, itemType, value, 0);
+      }
+      finally
+      {
+        if (lockedPtr != IntPtr.Zero) memMgr.Unlock(twCap.hContainer);
+      }
+      return twCap;
+    }
 
-    //        TWTY itemType = GetItemType<TValue>();
+    /// <summary>
+    /// Creates a <see cref="TW_CAPABILITY"/> with multiple values in an array container.
+    /// Caller will be responsible for ensuring memory is freed.
+    /// </summary>
+    /// <typeparam name="TValue"></typeparam>
+    /// <param name="cap"></param>
+    /// <param name="memMgr"></param>
+    /// <param name="values"></param>
+    /// <returns></returns>
+    public static TW_CAPABILITY CreateArrayCap<TValue>(this CAP cap, IMemoryManager memMgr, params TValue[] values) where TValue : struct
+    {
+      if (values == null) throw new ArgumentNullException(nameof(values));
 
-    //        // Allocate the container (go for worst case, which is TW_STR255)...
-    //        if (TwainPlatform.IsMacOSX)
-    //        {
-    //            // Allocate...
-    //            twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_ARRAY_MACOSX)) + ((values.Length + 1) * Marshal.SizeOf(default(TW_STR255)))));
-    //            lockedPtr = memMgr.Lock(twCap.hContainer);
+      TW_CAPABILITY twCap = new() { Cap = cap, ConType = TWON.ARRAY };
 
-    //            // Set the meta data...
-    //            TW_ARRAY_MACOSX twarraymacosx = default;
-    //            twarraymacosx.ItemType = (uint)itemType;
-    //            twarraymacosx.NumItems = (uint)values.Length;
-    //            Marshal.StructureToPtr(twarraymacosx, lockedPtr, false);
+      IntPtr lockedPtr = IntPtr.Zero;
+      try
+      {
+        //if (twCap.hContainer != IntPtr.Zero) memMgr.Free(ref twCap.hContainer);
 
-    //            // Get the pointer to the ItemList...
-    //            lockedPtr += Marshal.SizeOf(twarraymacosx);
-    //        }
-    //        else
-    //        {
-    //            // Allocate...
-    //            twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_ARRAY)) + ((values.Length + 1) * Marshal.SizeOf(default(TW_STR255)))));
-    //            lockedPtr = memMgr.Lock(twCap.hContainer);
+        TWTY itemType = GetItemType<TValue>();
 
-    //            // Set the meta data...
-    //            TW_ARRAY twarray = default;
-    //            twarray.ItemType = itemType;
-    //            twarray.NumItems = (uint)values.Length;
-    //            Marshal.StructureToPtr(twarray, lockedPtr, false);
+        // Allocate the container (go for worst case, which is TW_STR255)...
+        if (TwainPlatform.IsMacOSX)
+        {
+          // Allocate...
+          twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_ARRAY_MACOSX)) + ((values.Length + 1) * Marshal.SizeOf(default(TW_STR255)))));
+          lockedPtr = memMgr.Lock(twCap.hContainer);
 
-    //            // Get the pointer to the ItemList...
-    //            lockedPtr += Marshal.SizeOf(twarray);
-    //        }
+          // Set the meta data...
+          TW_ARRAY_MACOSX twarraymacosx = default;
+          twarraymacosx.ItemType = (uint)itemType;
+          twarraymacosx.NumItems = (uint)values.Length;
+          Marshal.StructureToPtr(twarraymacosx, lockedPtr, false);
 
-    //        // Set the ItemList...
-    //        for (var i = 0; i < values.Length; i++)
-    //        {
-    //            WriteContainerData(lockedPtr, itemType, values[i], i);
-    //        }
-    //    }
-    //    finally
-    //    {
-    //        if (lockedPtr != IntPtr.Zero) memMgr.Unlock(twCap.hContainer);
-    //    }
-    //}
+          // Get the pointer to the ItemList...
+          lockedPtr += Marshal.SizeOf(twarraymacosx);
+        }
+        else
+        {
+          // Allocate...
+          twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_ARRAY)) + ((values.Length + 1) * Marshal.SizeOf(default(TW_STR255)))));
+          lockedPtr = memMgr.Lock(twCap.hContainer);
 
-    //public static void WriteEnumContainer<TValue>(IMemoryManager memMgr, ref TW_CAPABILITY twCap, Enumeration<TValue> value) where TValue : struct
-    //{
-    //    IntPtr lockedPtr = IntPtr.Zero;
-    //    try
-    //    {
-    //        if (twCap.hContainer != IntPtr.Zero) memMgr.Free(ref twCap.hContainer);
+          // Set the meta data...
+          TW_ARRAY twarray = default;
+          twarray.ItemType = itemType;
+          twarray.NumItems = (uint)values.Length;
+          Marshal.StructureToPtr(twarray, lockedPtr, false);
 
-    //        TWTY itemType = GetItemType<TValue>();
+          // Get the pointer to the ItemList...
+          lockedPtr += Marshal.SizeOf(twarray);
+        }
 
-    //        // Allocate the container (go for worst case, which is TW_STR255)...
-    //        if (TwainPlatform.IsMacOSX)
-    //        {
-    //            // Allocate...
-    //            twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_ENUMERATION_MACOSX)) + ((value.Items.Length + 1) * Marshal.SizeOf(default(TW_STR255)))));
-    //            lockedPtr = memMgr.Lock(twCap.hContainer);
+        // Set the ItemList...
+        for (var i = 0; i < values.Length; i++)
+        {
+          WriteContainerData(lockedPtr, itemType, values[i], i);
+        }
+      }
+      finally
+      {
+        if (lockedPtr != IntPtr.Zero) memMgr.Unlock(twCap.hContainer);
+      }
+      return twCap;
+    }
 
-    //            // Set the meta data...
-    //            TW_ENUMERATION_MACOSX twenumerationmacosx = default;
-    //            twenumerationmacosx.ItemType = (uint)itemType;
-    //            twenumerationmacosx.NumItems = (uint)value.Items.Length;
-    //            twenumerationmacosx.CurrentIndex = (uint)value.CurrentIndex;
-    //            twenumerationmacosx.DefaultIndex = (uint)value.DefaultIndex;
-    //            Marshal.StructureToPtr(twenumerationmacosx, lockedPtr, false);
+    /// <summary>
+    /// Creates a <see cref="TW_CAPABILITY"/> with multiple values in an enum container.
+    /// Caller will be responsible for ensuring memory is freed.
+    /// </summary>
+    /// <typeparam name="TValue"></typeparam>
+    /// <param name="cap"></param>
+    /// <param name="memMgr"></param>
+    /// <param name="value"></param>
+    /// <returns></returns>
+    /// <exception cref="ArgumentException"></exception>
+    public static TW_CAPABILITY CreateEnumCap<TValue>(this CAP cap, IMemoryManager memMgr, Enumeration<TValue> value) where TValue : struct
+    {
+      if (value.Items == null) throw new ArgumentException("No items found in enumeration", nameof(value));
 
-    //            // Get the pointer to the ItemList...
-    //            lockedPtr += Marshal.SizeOf(twenumerationmacosx);
-    //        }
-    //        // Windows or the 2.4+ Linux DSM...
-    //        else if (TWAIN.GetPlatform() == Platform.WINDOWS ||
-    //            (twain.m_linuxdsm == TWAIN.LinuxDsm.IsLatestDsm) ||
-    //            ((twain.m_blFoundLatestDsm || twain.m_blFoundLatestDsm64) && (twain.m_linuxdsm == TWAIN.LinuxDsm.IsLatestDsm)))
-    //        {
-    //            // Allocate...
-    //            twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_ENUMERATION)) + ((value.Items.Length + 1) * Marshal.SizeOf(default(TW_STR255)))));
-    //            lockedPtr = memMgr.Lock(twCap.hContainer);
+      TW_CAPABILITY twCap = new() { Cap = cap, ConType = TWON.ENUMERATION };
 
-    //            // Set the meta data...
-    //            TW_ENUMERATION twenumeration = default;
-    //            twenumeration.ItemType = itemType;
-    //            twenumeration.NumItems = (uint)value.Items.Length;
-    //            twenumeration.CurrentIndex = (uint)value.CurrentIndex;
-    //            twenumeration.DefaultIndex = (uint)value.CurrentIndex;
-    //            Marshal.StructureToPtr(twenumeration, lockedPtr, false);
+      IntPtr lockedPtr = IntPtr.Zero;
+      try
+      {
+        //if (twCap.hContainer != IntPtr.Zero) memMgr.Free(ref twCap.hContainer);
 
-    //            // Get the pointer to the ItemList...
-    //            lockedPtr += Marshal.SizeOf(twenumeration);
-    //        }
-    //        // The -2.3 Linux DSM...
-    //        else
-    //        {
-    //            // Allocate...
-    //            twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_ENUMERATION_LINUX64)) + ((value.Items.Length + 1) * Marshal.SizeOf(default(TW_STR255)))));
-    //            lockedPtr = memMgr.Lock(twCap.hContainer);
+        TWTY itemType = GetItemType<TValue>();
 
-    //            // Set the meta data...
-    //            TW_ENUMERATION_LINUX64 twenumerationlinux64 = default;
-    //            twenumerationlinux64.ItemType = itemType;
-    //            twenumerationlinux64.NumItems = (ulong)value.Items.Length;
-    //            twenumerationlinux64.CurrentIndex = (ulong)value.CurrentIndex;
-    //            twenumerationlinux64.DefaultIndex = (ulong)value.CurrentIndex;
-    //            Marshal.StructureToPtr(twenumerationlinux64, lockedPtr, false);
+        // Allocate the container (go for worst case, which is TW_STR255)...
+        if (TwainPlatform.IsMacOSX)
+        {
+          // Allocate...
+          twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_ENUMERATION_MACOSX)) + ((value.Items.Length + 1) * Marshal.SizeOf(default(TW_STR255)))));
+          lockedPtr = memMgr.Lock(twCap.hContainer);
 
-    //            // Get the pointer to the ItemList...
-    //            lockedPtr += Marshal.SizeOf(twenumerationlinux64);
-    //        }
+          // Set the meta data...
+          TW_ENUMERATION_MACOSX twenumerationmacosx = default;
+          twenumerationmacosx.ItemType = (uint)itemType;
+          twenumerationmacosx.NumItems = (uint)value.Items.Length;
+          twenumerationmacosx.CurrentIndex = (uint)value.CurrentIndex;
+          twenumerationmacosx.DefaultIndex = (uint)value.DefaultIndex;
+          Marshal.StructureToPtr(twenumerationmacosx, lockedPtr, false);
 
-    //        // Set the ItemList...
-    //        for (var i = 0; i < value.Items.Length; i++)
-    //        {
-    //            WriteContainerData(lockedPtr, itemType, value.Items[i], i);
-    //        }
-    //    }
-    //    finally
-    //    {
-    //        if (lockedPtr != IntPtr.Zero) memMgr.Unlock(twCap.hContainer);
-    //    }
-    //}
+          // Get the pointer to the ItemList...
+          lockedPtr += Marshal.SizeOf(twenumerationmacosx);
+        }
+        // Windows or the 2.4+ Linux DSM...
+        else
+        {
+          // Allocate...
+          twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_ENUMERATION)) + ((value.Items.Length + 1) * Marshal.SizeOf(default(TW_STR255)))));
+          lockedPtr = memMgr.Lock(twCap.hContainer);
 
-    //public static void WriteRangeContainer<TValue>(IMemoryManager memMgr, ref TW_CAPABILITY twCap, Range<TValue> value) where TValue : struct
-    //{
-    //    IntPtr lockedPtr = IntPtr.Zero;
-    //    try
-    //    {
-    //        if (twCap.hContainer != IntPtr.Zero) memMgr.Free(ref twCap.hContainer);
+          // Set the meta data...
+          TW_ENUMERATION twenumeration = default;
+          twenumeration.ItemType = itemType;
+          twenumeration.NumItems = (uint)value.Items.Length;
+          twenumeration.CurrentIndex = (uint)value.CurrentIndex;
+          twenumeration.DefaultIndex = (uint)value.CurrentIndex;
+          Marshal.StructureToPtr(twenumeration, lockedPtr, false);
 
-    //        TWTY itemType = GetItemType<TValue>();
+          // Get the pointer to the ItemList...
+          lockedPtr += Marshal.SizeOf(twenumeration);
+        }
+        // The -2.3 Linux DSM...
+        //else
+        //{
+        //  // Allocate...
+        //  twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_ENUMERATION_LINUX64)) + ((value.Items.Length + 1) * Marshal.SizeOf(default(TW_STR255)))));
+        //  lockedPtr = memMgr.Lock(twCap.hContainer);
 
-    //        // Allocate the container (go for worst case, which is TW_STR255)...
-    //        if (TwainPlatform.IsMacOSX)
-    //        {
-    //            // Allocate...
-    //            twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_RANGE_MACOSX))));
-    //            lockedPtr = memMgr.Lock(twCap.hContainer);
-    //        }
-    //        // Windows or the 2.4+ Linux DSM...
-    //        else if (TWAIN.GetPlatform() == Platform.WINDOWS ||
-    //            (twain.m_linuxdsm == TWAIN.LinuxDsm.IsLatestDsm) ||
-    //            ((twain.m_blFoundLatestDsm || twain.m_blFoundLatestDsm64) && (twain.m_linuxdsm == TWAIN.LinuxDsm.IsLatestDsm)))
-    //        {
-    //            // Allocate...
-    //            twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_RANGE))));
-    //            lockedPtr = memMgr.Lock(twCap.hContainer);
-    //        }
-    //        // The -2.3 Linux DSM...
-    //        else
-    //        {
-    //            // Allocate...
-    //            twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_RANGE_LINUX64))));
-    //            lockedPtr = memMgr.Lock(twCap.hContainer);
-    //        }
+        //  // Set the meta data...
+        //  TW_ENUMERATION_LINUX64 twenumerationlinux64 = default;
+        //  twenumerationlinux64.ItemType = itemType;
+        //  twenumerationlinux64.NumItems = (ulong)value.Items.Length;
+        //  twenumerationlinux64.CurrentIndex = (ulong)value.CurrentIndex;
+        //  twenumerationlinux64.DefaultIndex = (ulong)value.CurrentIndex;
+        //  Marshal.StructureToPtr(twenumerationlinux64, lockedPtr, false);
 
-    //        // Set the Item...
-    //        WriteRangeValues(twain, lockedPtr, itemType, value);
-    //    }
-    //    finally
-    //    {
-    //        if (lockedPtr != IntPtr.Zero) memMgr.Unlock(twCap.hContainer);
-    //    }
-    //}
+        //  // Get the pointer to the ItemList...
+        //  lockedPtr += Marshal.SizeOf(twenumerationlinux64);
+        //}
 
-    //static void WriteRangeValues<TValue>(IMemoryManager memMgr, IntPtr lockedPtr, TWTY itemType, Range<TValue> value) where TValue : struct
-    //{
-    //    // TODO: reduce this later
+        // Set the ItemList...
+        for (var i = 0; i < value.Items.Length; i++)
+        {
+          WriteContainerData(lockedPtr, itemType, value.Items[i], i);
+        }
+      }
+      finally
+      {
+        if (lockedPtr != IntPtr.Zero) memMgr.Unlock(twCap.hContainer);
+      }
+      return twCap;
+    }
 
-    //    TW_RANGE twrange = default;
-    //    TW_RANGE_MACOSX twrangemacosx = default;
-    //    TW_RANGE_LINUX64 twrangelinux64 = default;
+    /// <summary>
+    /// Creates a <see cref="TW_CAPABILITY"/> with multiple values in a range container.
+    /// Caller will be responsible for ensuring memory is freed.
+    /// </summary>
+    /// <typeparam name="TValue"></typeparam>
+    /// <param name="cap"></param>
+    /// <param name="memMgr"></param>
+    /// <param name="value"></param>
+    /// <returns></returns>
+    public static TW_CAPABILITY CreateRangeCap<TValue>(this CAP cap, IMemoryManager memMgr, Range<TValue> value) where TValue : struct
+    {
+      TW_CAPABILITY twCap = new() { Cap = cap, ConType = TWON.ENUMERATION };
 
-    //    switch (itemType)
-    //    {
-    //        default:
-    //            throw new NotSupportedException($"{itemType} is not supported for range.");
-    //        case TWTY.INT8:
-    //            if (TwainPlatform.IsMacOSX)
-    //            {
-    //                twrangemacosx.ItemType = (uint)itemType;
-    //                twrangemacosx.MinValue = (uint)Convert.ToSByte(value.MinValue);
-    //                twrangemacosx.MaxValue = (uint)Convert.ToSByte(value.MaxValue);
-    //                twrangemacosx.StepSize = (uint)Convert.ToSByte(value.StepSize);
-    //                twrangemacosx.DefaultValue = (uint)Convert.ToSByte(value.DefaultValue);
-    //                twrangemacosx.CurrentValue = (uint)Convert.ToSByte(value.CurrentValue);
-    //                Marshal.StructureToPtr(twrangemacosx, lockedPtr, false);
-    //            }
-    //            else if ((twain.m_linuxdsm == TWAIN.LinuxDsm.Unknown) || (twain.m_linuxdsm == TWAIN.LinuxDsm.IsLatestDsm))
-    //            {
-    //                twrange.ItemType = itemType;
-    //                twrange.MinValue = (uint)Convert.ToSByte(value.MinValue);
-    //                twrange.MaxValue = (uint)Convert.ToSByte(value.MaxValue);
-    //                twrange.StepSize = (uint)Convert.ToSByte(value.StepSize);
-    //                twrange.DefaultValue = (uint)Convert.ToSByte(value.DefaultValue);
-    //                twrange.CurrentValue = (uint)Convert.ToSByte(value.CurrentValue);
-    //                Marshal.StructureToPtr(twrange, lockedPtr, false);
-    //            }
-    //            else
-    //            {
-    //                twrangelinux64.ItemType = itemType;
-    //                twrangelinux64.MinValue = (uint)Convert.ToSByte(value.MinValue);
-    //                twrangelinux64.MaxValue = (uint)Convert.ToSByte(value.MaxValue);
-    //                twrangelinux64.StepSize = (uint)Convert.ToSByte(value.StepSize);
-    //                twrangelinux64.DefaultValue = (uint)Convert.ToSByte(value.DefaultValue);
-    //                twrangelinux64.CurrentValue = (uint)Convert.ToSByte(value.CurrentValue);
-    //                Marshal.StructureToPtr(twrangelinux64, lockedPtr, false);
-    //            }
-    //            break;
-    //        case TWTY.UINT8:
-    //            if (TwainPlatform.IsMacOSX)
-    //            {
-    //                twrangemacosx.ItemType = (uint)itemType;
-    //                twrangemacosx.MinValue = Convert.ToByte(value.MinValue);
-    //                twrangemacosx.MaxValue = Convert.ToByte(value.MaxValue);
-    //                twrangemacosx.StepSize = Convert.ToByte(value.StepSize);
-    //                twrangemacosx.DefaultValue = Convert.ToByte(value.DefaultValue);
-    //                twrangemacosx.CurrentValue = Convert.ToByte(value.CurrentValue);
-    //                Marshal.StructureToPtr(twrangemacosx, lockedPtr, false);
-    //            }
-    //            else if ((twain.m_linuxdsm == TWAIN.LinuxDsm.Unknown) || (twain.m_linuxdsm == TWAIN.LinuxDsm.IsLatestDsm))
-    //            {
-    //                twrange.ItemType = itemType;
-    //                twrange.MinValue = Convert.ToByte(value.MinValue);
-    //                twrange.MaxValue = Convert.ToByte(value.MaxValue);
-    //                twrange.StepSize = Convert.ToByte(value.StepSize);
-    //                twrange.DefaultValue = Convert.ToByte(value.DefaultValue);
-    //                twrange.CurrentValue = Convert.ToByte(value.CurrentValue);
-    //                Marshal.StructureToPtr(twrange, lockedPtr, false);
-    //            }
-    //            else
-    //            {
-    //                twrangelinux64.ItemType = itemType;
-    //                twrangelinux64.MinValue = Convert.ToByte(value.MinValue);
-    //                twrangelinux64.MaxValue = Convert.ToByte(value.MaxValue);
-    //                twrangelinux64.StepSize = Convert.ToByte(value.StepSize);
-    //                twrangelinux64.DefaultValue = Convert.ToByte(value.DefaultValue);
-    //                twrangelinux64.CurrentValue = Convert.ToByte(value.CurrentValue);
-    //                Marshal.StructureToPtr(twrangelinux64, lockedPtr, false);
-    //            }
-    //            break;
-    //        case TWTY.INT16:
-    //            if (TwainPlatform.IsMacOSX)
-    //            {
-    //                twrangemacosx.ItemType = (uint)itemType;
-    //                twrangemacosx.MinValue = (uint)Convert.ToInt16(value.MinValue);
-    //                twrangemacosx.MaxValue = (uint)Convert.ToInt16(value.MaxValue);
-    //                twrangemacosx.StepSize = (uint)Convert.ToInt16(value.StepSize);
-    //                twrangemacosx.DefaultValue = (uint)Convert.ToInt16(value.DefaultValue);
-    //                twrangemacosx.CurrentValue = (uint)Convert.ToInt16(value.CurrentValue);
-    //                Marshal.StructureToPtr(twrangemacosx, lockedPtr, false);
-    //            }
-    //            else if ((twain.m_linuxdsm == TWAIN.LinuxDsm.Unknown) || (twain.m_linuxdsm == TWAIN.LinuxDsm.IsLatestDsm))
-    //            {
-    //                twrange.ItemType = itemType;
-    //                twrange.MinValue = (uint)Convert.ToInt16(value.MinValue);
-    //                twrange.MaxValue = (uint)Convert.ToInt16(value.MaxValue);
-    //                twrange.StepSize = (uint)Convert.ToInt16(value.StepSize);
-    //                twrange.DefaultValue = (uint)Convert.ToInt16(value.DefaultValue);
-    //                twrange.CurrentValue = (uint)Convert.ToInt16(value.CurrentValue);
-    //                Marshal.StructureToPtr(twrange, lockedPtr, false);
-    //            }
-    //            else
-    //            {
-    //                twrangelinux64.ItemType = itemType;
-    //                twrangelinux64.MinValue = (uint)Convert.ToInt16(value.MinValue);
-    //                twrangelinux64.MaxValue = (uint)Convert.ToInt16(value.MaxValue);
-    //                twrangelinux64.StepSize = (uint)Convert.ToInt16(value.StepSize);
-    //                twrangelinux64.DefaultValue = (uint)Convert.ToInt16(value.DefaultValue);
-    //                twrangelinux64.CurrentValue = (uint)Convert.ToInt16(value.CurrentValue);
-    //                Marshal.StructureToPtr(twrangelinux64, lockedPtr, false);
-    //            }
-    //            break;
-    //        case TWTY.BOOL:
-    //        case TWTY.UINT16:
-    //            if (TwainPlatform.IsMacOSX)
-    //            {
-    //                twrangemacosx.ItemType = (uint)itemType;
-    //                twrangemacosx.MinValue = Convert.ToUInt16(value.MinValue);
-    //                twrangemacosx.MaxValue = Convert.ToUInt16(value.MaxValue);
-    //                twrangemacosx.StepSize = Convert.ToUInt16(value.StepSize);
-    //                twrangemacosx.DefaultValue = Convert.ToUInt16(value.DefaultValue);
-    //                twrangemacosx.CurrentValue = Convert.ToUInt16(value.CurrentValue);
-    //                Marshal.StructureToPtr(twrangemacosx, lockedPtr, false);
-    //            }
-    //            else if ((twain.m_linuxdsm == TWAIN.LinuxDsm.Unknown) || (twain.m_linuxdsm == TWAIN.LinuxDsm.IsLatestDsm))
-    //            {
-    //                twrange.ItemType = itemType;
-    //                twrange.MinValue = Convert.ToUInt16(value.MinValue);
-    //                twrange.MaxValue = Convert.ToUInt16(value.MaxValue);
-    //                twrange.StepSize = Convert.ToUInt16(value.StepSize);
-    //                twrange.DefaultValue = Convert.ToUInt16(value.DefaultValue);
-    //                twrange.CurrentValue = Convert.ToUInt16(value.CurrentValue);
-    //                Marshal.StructureToPtr(twrange, lockedPtr, false);
-    //            }
-    //            else
-    //            {
-    //                twrangelinux64.ItemType = itemType;
-    //                twrangelinux64.MinValue = Convert.ToUInt16(value.MinValue);
-    //                twrangelinux64.MaxValue = Convert.ToUInt16(value.MaxValue);
-    //                twrangelinux64.StepSize = Convert.ToUInt16(value.StepSize);
-    //                twrangelinux64.DefaultValue = Convert.ToUInt16(value.DefaultValue);
-    //                twrangelinux64.CurrentValue = Convert.ToUInt16(value.CurrentValue);
-    //                Marshal.StructureToPtr(twrangelinux64, lockedPtr, false);
-    //            }
-    //            break;
-    //        case TWTY.INT32:
-    //            if (TwainPlatform.IsMacOSX)
-    //            {
-    //                twrangemacosx.ItemType = (uint)itemType;
-    //                twrangemacosx.MinValue = (uint)Convert.ToInt32(value.MinValue);
-    //                twrangemacosx.MaxValue = (uint)Convert.ToInt32(value.MaxValue);
-    //                twrangemacosx.StepSize = (uint)Convert.ToInt32(value.StepSize);
-    //                twrangemacosx.DefaultValue = (uint)Convert.ToInt32(value.DefaultValue);
-    //                twrangemacosx.CurrentValue = (uint)Convert.ToInt32(value.CurrentValue);
-    //                Marshal.StructureToPtr(twrangemacosx, lockedPtr, false);
-    //            }
-    //            else if ((twain.m_linuxdsm == TWAIN.LinuxDsm.Unknown) || (twain.m_linuxdsm == TWAIN.LinuxDsm.IsLatestDsm))
-    //            {
-    //                twrange.ItemType = itemType;
-    //                twrange.MinValue = (uint)Convert.ToInt32(value.MinValue);
-    //                twrange.MaxValue = (uint)Convert.ToInt32(value.MaxValue);
-    //                twrange.StepSize = (uint)Convert.ToInt32(value.StepSize);
-    //                twrange.DefaultValue = (uint)Convert.ToInt32(value.DefaultValue);
-    //                twrange.CurrentValue = (uint)Convert.ToInt32(value.CurrentValue);
-    //                Marshal.StructureToPtr(twrange, lockedPtr, false);
-    //            }
-    //            else
-    //            {
-    //                twrangelinux64.ItemType = itemType;
-    //                twrangelinux64.MinValue = (uint)Convert.ToInt32(value.MinValue);
-    //                twrangelinux64.MaxValue = (uint)Convert.ToInt32(value.MaxValue);
-    //                twrangelinux64.StepSize = (uint)Convert.ToInt32(value.StepSize);
-    //                twrangelinux64.DefaultValue = (uint)Convert.ToInt32(value.DefaultValue);
-    //                twrangelinux64.CurrentValue = (uint)Convert.ToInt32(value.CurrentValue);
-    //                Marshal.StructureToPtr(twrangelinux64, lockedPtr, false);
-    //            }
-    //            break;
-    //        case TWTY.UINT32:
-    //            if (TwainPlatform.IsMacOSX)
-    //            {
-    //                twrangemacosx.ItemType = (uint)itemType;
-    //                twrangemacosx.MinValue = Convert.ToUInt32(value.MinValue);
-    //                twrangemacosx.MaxValue = Convert.ToUInt32(value.MaxValue);
-    //                twrangemacosx.StepSize = Convert.ToUInt32(value.StepSize);
-    //                twrangemacosx.DefaultValue = Convert.ToUInt32(value.DefaultValue);
-    //                twrangemacosx.CurrentValue = Convert.ToUInt32(value.CurrentValue);
-    //                Marshal.StructureToPtr(twrangemacosx, lockedPtr, false);
-    //            }
-    //            else if ((twain.m_linuxdsm == TWAIN.LinuxDsm.Unknown) || (twain.m_linuxdsm == TWAIN.LinuxDsm.IsLatestDsm))
-    //            {
-    //                twrange.ItemType = itemType;
-    //                twrange.MinValue = Convert.ToUInt32(value.MinValue);
-    //                twrange.MaxValue = Convert.ToUInt32(value.MaxValue);
-    //                twrange.StepSize = Convert.ToUInt32(value.StepSize);
-    //                twrange.DefaultValue = Convert.ToUInt32(value.DefaultValue);
-    //                twrange.CurrentValue = Convert.ToUInt32(value.CurrentValue);
-    //                Marshal.StructureToPtr(twrange, lockedPtr, false);
-    //            }
-    //            else
-    //            {
-    //                twrangelinux64.ItemType = itemType;
-    //                twrangelinux64.MinValue = Convert.ToUInt32(value.MinValue);
-    //                twrangelinux64.MaxValue = Convert.ToUInt32(value.MaxValue);
-    //                twrangelinux64.StepSize = Convert.ToUInt32(value.StepSize);
-    //                twrangelinux64.DefaultValue = Convert.ToUInt32(value.DefaultValue);
-    //                twrangelinux64.CurrentValue = Convert.ToUInt32(value.CurrentValue);
-    //                Marshal.StructureToPtr(twrangelinux64, lockedPtr, false);
-    //            }
-    //            break;
-    //        case TWTY.FIX32:
-    //            double min = Convert.ToDouble(value.MinValue);
-    //            double max = Convert.ToDouble(value.MaxValue);
-    //            double step = Convert.ToDouble(value.StepSize);
-    //            double def = Convert.ToDouble(value.DefaultValue);
-    //            double current = Convert.ToDouble(value.CurrentValue);
-    //            if (TwainPlatform.IsMacOSX)
-    //            {
-    //                TW_RANGE_FIX32_MACOSX twrangefix32macosx = default;
-    //                twrangefix32macosx.ItemType = (uint)itemType;
-    //                twrangefix32macosx.MinValue = new TW_FIX32(min);
-    //                twrangefix32macosx.MaxValue = new TW_FIX32(max);
-    //                twrangefix32macosx.StepSize = new TW_FIX32(step);
-    //                twrangefix32macosx.DefaultValue = new TW_FIX32(def);
-    //                twrangefix32macosx.CurrentValue = new TW_FIX32(current);
-    //                Marshal.StructureToPtr(twrangefix32macosx, lockedPtr, false);
-    //            }
-    //            else
-    //            {
-    //                TW_RANGE_FIX32 twrangefix32 = default;
-    //                twrangefix32.ItemType = itemType;
-    //                twrangefix32.MinValue = new TW_FIX32(min);
-    //                twrangefix32.MaxValue = new TW_FIX32(max);
-    //                twrangefix32.StepSize = new TW_FIX32(step);
-    //                twrangefix32.DefaultValue = new TW_FIX32(def);
-    //                twrangefix32.CurrentValue = new TW_FIX32(current);
-    //                Marshal.StructureToPtr(twrangefix32, lockedPtr, false);
-    //            }
-    //            break;
-    //    }
-    //}
+      IntPtr lockedPtr = IntPtr.Zero;
+      try
+      {
+        //if (twCap.hContainer != IntPtr.Zero) memMgr.Free(ref twCap.hContainer);
 
-    //static TWTY GetItemType<TValue>() where TValue : struct
-    //{
-    //    var type = typeof(TValue);
-    //    if (type == typeof(BoolType)) return TWTY.BOOL;
-    //    if (type == typeof(TW_FIX32)) return TWTY.FIX32;
-    //    if (type == typeof(TW_STR32)) return TWTY.STR32;
-    //    if (type == typeof(TW_STR64)) return TWTY.STR64;
-    //    if (type == typeof(TW_STR128)) return TWTY.STR128;
-    //    if (type == typeof(TW_STR255)) return TWTY.STR255;
-    //    if (type == typeof(TW_FRAME)) return TWTY.FRAME;
+        TWTY itemType = GetItemType<TValue>();
 
-    //    if (type.IsEnum)
-    //    {
-    //        type = type.GetEnumUnderlyingType();
-    //    }
+        // Allocate the container (go for worst case, which is TW_STR255)...
+        if (TwainPlatform.IsMacOSX)
+        {
+          // Allocate...
+          twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_RANGE_MACOSX))));
+          lockedPtr = memMgr.Lock(twCap.hContainer);
+        }
+        // Windows or the 2.4+ Linux DSM...
+        else
+        {
+          // Allocate...
+          twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_RANGE))));
+          lockedPtr = memMgr.Lock(twCap.hContainer);
+        }
+        //// The -2.3 Linux DSM...
+        //else
+        //{
+        //  // Allocate...
+        //  twCap.hContainer = memMgr.Alloc((uint)(Marshal.SizeOf(default(TW_RANGE_LINUX64))));
+        //  lockedPtr = memMgr.Lock(twCap.hContainer);
+        //}
 
-    //    if (type == typeof(ushort)) return TWTY.UINT16;
-    //    if (type == typeof(short)) return TWTY.INT16;
-    //    if (type == typeof(uint)) return TWTY.UINT32;
-    //    if (type == typeof(int)) return TWTY.INT32;
-    //    if (type == typeof(byte)) return TWTY.UINT8;
-    //    if (type == typeof(sbyte)) return TWTY.INT8;
+        // Set the Item...
+        WriteRangeValues(memMgr, lockedPtr, itemType, value);
+      }
+      finally
+      {
+        if (lockedPtr != IntPtr.Zero) memMgr.Unlock(twCap.hContainer);
+      }
+      return twCap;
+    }
 
-    //    throw new NotSupportedException($"{type.Name} is not supported for writing.");
-    //}
+    static void WriteRangeValues<TValue>(IMemoryManager memMgr, IntPtr lockedPtr, TWTY itemType, Range<TValue> value) where TValue : struct
+    {
+      // TODO: reduce this later
 
-    ///// <summary>
-    ///// Writes single piece of value to the container pointer.
-    ///// </summary>
-    ///// <typeparam name="TValue"></typeparam>
-    ///// <param name="intptr">A locked pointer to the container's data pointer. If data is array this is the 0th item.</param>
-    ///// <param name="type">The twain type.</param>
-    ///// <param name="value"></param>
-    ///// <param name="itemIndex">Index of the item if pointer is array.</param>
-    //static void WriteContainerData<TValue>(IntPtr intptr, TWTY type, TValue value, int itemIndex) where TValue : struct
-    //{
-    //    switch (type)
-    //    {
-    //        default:
-    //            throw new NotSupportedException($"Unsupported item type {type} for writing.");
-    //        // TODO: for small types needs to fill whole int32 before writing?
-    //        case TWTY.INT8:
-    //            intptr += 1 * itemIndex;
-    //            //int intval = Convert.ToSByte(value);
-    //            //Marshal.StructureToPtr(intval, intptr, false);
-    //            Marshal.StructureToPtr(Convert.ToSByte(value), intptr, false);
-    //            break;
-    //        case TWTY.UINT8:
-    //            intptr += 1 * itemIndex;
-    //            //uint uintval = Convert.ToByte(value);
-    //            //Marshal.StructureToPtr(uintval, intptr, false);
-    //            Marshal.StructureToPtr(Convert.ToByte(value), intptr, false);
-    //            break;
-    //        case TWTY.INT16:
-    //            intptr += 2 * itemIndex;
-    //            //intval = Convert.ToInt16(value);
-    //            //Marshal.StructureToPtr(intval, intptr, false);
-    //            Marshal.StructureToPtr(Convert.ToInt16(value), intptr, false);
-    //            break;
-    //        case TWTY.BOOL:
-    //        case TWTY.UINT16:
-    //            intptr += 2 * itemIndex;
-    //            //uintval = Convert.ToUInt16(value);
-    //            //Marshal.StructureToPtr(uintval, intptr, false);
-    //            Marshal.StructureToPtr(Convert.ToUInt16(value), intptr, false);
-    //            break;
-    //        case TWTY.INT32:
-    //            intptr += 4 * itemIndex;
-    //            Marshal.StructureToPtr(Convert.ToInt32(value), intptr, false);
-    //            break;
-    //        case TWTY.UINT32:
-    //            intptr += 4 * itemIndex;
-    //            Marshal.StructureToPtr(Convert.ToUInt32(value), intptr, false);
-    //            break;
-    //        case TWTY.FIX32:
-    //            intptr += 4 * itemIndex;
-    //            Marshal.StructureToPtr(value, intptr, false);
-    //            break;
-    //        case TWTY.FRAME:
-    //            intptr += 16 * itemIndex;
-    //            Marshal.StructureToPtr(value, intptr, false);
-    //            break;
-    //        case TWTY.STR32:
-    //            intptr += TW_STR32.Size * itemIndex;
-    //            Marshal.StructureToPtr(value, intptr, false);
-    //            break;
-    //        case TWTY.STR64:
-    //            intptr += TW_STR64.Size * itemIndex;
-    //            Marshal.StructureToPtr(value, intptr, false);
-    //            break;
-    //        case TWTY.STR128:
-    //            intptr += TW_STR128.Size * itemIndex;
-    //            Marshal.StructureToPtr(value, intptr, false);
-    //            break;
-    //        case TWTY.STR255:
-    //            intptr += TW_STR255.Size * itemIndex;
-    //            Marshal.StructureToPtr(value, intptr, false);
-    //            break;
-    //    }
-    //}
+      TW_RANGE twrange = default;
+      TW_RANGE_MACOSX twrangemacosx = default;
+      //TW_RANGE_LINUX64 twrangelinux64 = default;
+
+      switch (itemType)
+      {
+        default:
+          throw new NotSupportedException($"{itemType} is not supported for range.");
+        case TWTY.INT8:
+          if (TwainPlatform.IsMacOSX)
+          {
+            twrangemacosx.ItemType = (uint)itemType;
+            twrangemacosx.MinValue = (uint)Convert.ToSByte(value.MinValue);
+            twrangemacosx.MaxValue = (uint)Convert.ToSByte(value.MaxValue);
+            twrangemacosx.StepSize = (uint)Convert.ToSByte(value.StepSize);
+            twrangemacosx.DefaultValue = (uint)Convert.ToSByte(value.DefaultValue);
+            twrangemacosx.CurrentValue = (uint)Convert.ToSByte(value.CurrentValue);
+            Marshal.StructureToPtr(twrangemacosx, lockedPtr, false);
+          }
+          else //if ((twain.m_linuxdsm == TWAIN.LinuxDsm.Unknown) || (twain.m_linuxdsm == TWAIN.LinuxDsm.IsLatestDsm))
+          {
+            twrange.ItemType = itemType;
+            twrange.MinValue = (uint)Convert.ToSByte(value.MinValue);
+            twrange.MaxValue = (uint)Convert.ToSByte(value.MaxValue);
+            twrange.StepSize = (uint)Convert.ToSByte(value.StepSize);
+            twrange.DefaultValue = (uint)Convert.ToSByte(value.DefaultValue);
+            twrange.CurrentValue = (uint)Convert.ToSByte(value.CurrentValue);
+            Marshal.StructureToPtr(twrange, lockedPtr, false);
+          }
+          //else
+          //{
+          //  twrangelinux64.ItemType = itemType;
+          //  twrangelinux64.MinValue = (uint)Convert.ToSByte(value.MinValue);
+          //  twrangelinux64.MaxValue = (uint)Convert.ToSByte(value.MaxValue);
+          //  twrangelinux64.StepSize = (uint)Convert.ToSByte(value.StepSize);
+          //  twrangelinux64.DefaultValue = (uint)Convert.ToSByte(value.DefaultValue);
+          //  twrangelinux64.CurrentValue = (uint)Convert.ToSByte(value.CurrentValue);
+          //  Marshal.StructureToPtr(twrangelinux64, lockedPtr, false);
+          //}
+          break;
+        case TWTY.UINT8:
+          if (TwainPlatform.IsMacOSX)
+          {
+            twrangemacosx.ItemType = (uint)itemType;
+            twrangemacosx.MinValue = Convert.ToByte(value.MinValue);
+            twrangemacosx.MaxValue = Convert.ToByte(value.MaxValue);
+            twrangemacosx.StepSize = Convert.ToByte(value.StepSize);
+            twrangemacosx.DefaultValue = Convert.ToByte(value.DefaultValue);
+            twrangemacosx.CurrentValue = Convert.ToByte(value.CurrentValue);
+            Marshal.StructureToPtr(twrangemacosx, lockedPtr, false);
+          }
+          else //if ((twain.m_linuxdsm == TWAIN.LinuxDsm.Unknown) || (twain.m_linuxdsm == TWAIN.LinuxDsm.IsLatestDsm))
+          {
+            twrange.ItemType = itemType;
+            twrange.MinValue = Convert.ToByte(value.MinValue);
+            twrange.MaxValue = Convert.ToByte(value.MaxValue);
+            twrange.StepSize = Convert.ToByte(value.StepSize);
+            twrange.DefaultValue = Convert.ToByte(value.DefaultValue);
+            twrange.CurrentValue = Convert.ToByte(value.CurrentValue);
+            Marshal.StructureToPtr(twrange, lockedPtr, false);
+          }
+          //else
+          //{
+          //  twrangelinux64.ItemType = itemType;
+          //  twrangelinux64.MinValue = Convert.ToByte(value.MinValue);
+          //  twrangelinux64.MaxValue = Convert.ToByte(value.MaxValue);
+          //  twrangelinux64.StepSize = Convert.ToByte(value.StepSize);
+          //  twrangelinux64.DefaultValue = Convert.ToByte(value.DefaultValue);
+          //  twrangelinux64.CurrentValue = Convert.ToByte(value.CurrentValue);
+          //  Marshal.StructureToPtr(twrangelinux64, lockedPtr, false);
+          //}
+          break;
+        case TWTY.INT16:
+          if (TwainPlatform.IsMacOSX)
+          {
+            twrangemacosx.ItemType = (uint)itemType;
+            twrangemacosx.MinValue = (uint)Convert.ToInt16(value.MinValue);
+            twrangemacosx.MaxValue = (uint)Convert.ToInt16(value.MaxValue);
+            twrangemacosx.StepSize = (uint)Convert.ToInt16(value.StepSize);
+            twrangemacosx.DefaultValue = (uint)Convert.ToInt16(value.DefaultValue);
+            twrangemacosx.CurrentValue = (uint)Convert.ToInt16(value.CurrentValue);
+            Marshal.StructureToPtr(twrangemacosx, lockedPtr, false);
+          }
+          else // if ((twain.m_linuxdsm == TWAIN.LinuxDsm.Unknown) || (twain.m_linuxdsm == TWAIN.LinuxDsm.IsLatestDsm))
+          {
+            twrange.ItemType = itemType;
+            twrange.MinValue = (uint)Convert.ToInt16(value.MinValue);
+            twrange.MaxValue = (uint)Convert.ToInt16(value.MaxValue);
+            twrange.StepSize = (uint)Convert.ToInt16(value.StepSize);
+            twrange.DefaultValue = (uint)Convert.ToInt16(value.DefaultValue);
+            twrange.CurrentValue = (uint)Convert.ToInt16(value.CurrentValue);
+            Marshal.StructureToPtr(twrange, lockedPtr, false);
+          }
+          //else
+          //{
+          //  twrangelinux64.ItemType = itemType;
+          //  twrangelinux64.MinValue = (uint)Convert.ToInt16(value.MinValue);
+          //  twrangelinux64.MaxValue = (uint)Convert.ToInt16(value.MaxValue);
+          //  twrangelinux64.StepSize = (uint)Convert.ToInt16(value.StepSize);
+          //  twrangelinux64.DefaultValue = (uint)Convert.ToInt16(value.DefaultValue);
+          //  twrangelinux64.CurrentValue = (uint)Convert.ToInt16(value.CurrentValue);
+          //  Marshal.StructureToPtr(twrangelinux64, lockedPtr, false);
+          //}
+          break;
+        case TWTY.BOOL:
+        case TWTY.UINT16:
+          if (TwainPlatform.IsMacOSX)
+          {
+            twrangemacosx.ItemType = (uint)itemType;
+            twrangemacosx.MinValue = Convert.ToUInt16(value.MinValue);
+            twrangemacosx.MaxValue = Convert.ToUInt16(value.MaxValue);
+            twrangemacosx.StepSize = Convert.ToUInt16(value.StepSize);
+            twrangemacosx.DefaultValue = Convert.ToUInt16(value.DefaultValue);
+            twrangemacosx.CurrentValue = Convert.ToUInt16(value.CurrentValue);
+            Marshal.StructureToPtr(twrangemacosx, lockedPtr, false);
+          }
+          else //if ((twain.m_linuxdsm == TWAIN.LinuxDsm.Unknown) || (twain.m_linuxdsm == TWAIN.LinuxDsm.IsLatestDsm))
+          {
+            twrange.ItemType = itemType;
+            twrange.MinValue = Convert.ToUInt16(value.MinValue);
+            twrange.MaxValue = Convert.ToUInt16(value.MaxValue);
+            twrange.StepSize = Convert.ToUInt16(value.StepSize);
+            twrange.DefaultValue = Convert.ToUInt16(value.DefaultValue);
+            twrange.CurrentValue = Convert.ToUInt16(value.CurrentValue);
+            Marshal.StructureToPtr(twrange, lockedPtr, false);
+          }
+          //else
+          //{
+          //  twrangelinux64.ItemType = itemType;
+          //  twrangelinux64.MinValue = Convert.ToUInt16(value.MinValue);
+          //  twrangelinux64.MaxValue = Convert.ToUInt16(value.MaxValue);
+          //  twrangelinux64.StepSize = Convert.ToUInt16(value.StepSize);
+          //  twrangelinux64.DefaultValue = Convert.ToUInt16(value.DefaultValue);
+          //  twrangelinux64.CurrentValue = Convert.ToUInt16(value.CurrentValue);
+          //  Marshal.StructureToPtr(twrangelinux64, lockedPtr, false);
+          //}
+          break;
+        case TWTY.INT32:
+          if (TwainPlatform.IsMacOSX)
+          {
+            twrangemacosx.ItemType = (uint)itemType;
+            twrangemacosx.MinValue = (uint)Convert.ToInt32(value.MinValue);
+            twrangemacosx.MaxValue = (uint)Convert.ToInt32(value.MaxValue);
+            twrangemacosx.StepSize = (uint)Convert.ToInt32(value.StepSize);
+            twrangemacosx.DefaultValue = (uint)Convert.ToInt32(value.DefaultValue);
+            twrangemacosx.CurrentValue = (uint)Convert.ToInt32(value.CurrentValue);
+            Marshal.StructureToPtr(twrangemacosx, lockedPtr, false);
+          }
+          else //if ((twain.m_linuxdsm == TWAIN.LinuxDsm.Unknown) || (twain.m_linuxdsm == TWAIN.LinuxDsm.IsLatestDsm))
+          {
+            twrange.ItemType = itemType;
+            twrange.MinValue = (uint)Convert.ToInt32(value.MinValue);
+            twrange.MaxValue = (uint)Convert.ToInt32(value.MaxValue);
+            twrange.StepSize = (uint)Convert.ToInt32(value.StepSize);
+            twrange.DefaultValue = (uint)Convert.ToInt32(value.DefaultValue);
+            twrange.CurrentValue = (uint)Convert.ToInt32(value.CurrentValue);
+            Marshal.StructureToPtr(twrange, lockedPtr, false);
+          }
+          //else
+          //{
+          //  twrangelinux64.ItemType = itemType;
+          //  twrangelinux64.MinValue = (uint)Convert.ToInt32(value.MinValue);
+          //  twrangelinux64.MaxValue = (uint)Convert.ToInt32(value.MaxValue);
+          //  twrangelinux64.StepSize = (uint)Convert.ToInt32(value.StepSize);
+          //  twrangelinux64.DefaultValue = (uint)Convert.ToInt32(value.DefaultValue);
+          //  twrangelinux64.CurrentValue = (uint)Convert.ToInt32(value.CurrentValue);
+          //  Marshal.StructureToPtr(twrangelinux64, lockedPtr, false);
+          //}
+          break;
+        case TWTY.UINT32:
+          if (TwainPlatform.IsMacOSX)
+          {
+            twrangemacosx.ItemType = (uint)itemType;
+            twrangemacosx.MinValue = Convert.ToUInt32(value.MinValue);
+            twrangemacosx.MaxValue = Convert.ToUInt32(value.MaxValue);
+            twrangemacosx.StepSize = Convert.ToUInt32(value.StepSize);
+            twrangemacosx.DefaultValue = Convert.ToUInt32(value.DefaultValue);
+            twrangemacosx.CurrentValue = Convert.ToUInt32(value.CurrentValue);
+            Marshal.StructureToPtr(twrangemacosx, lockedPtr, false);
+          }
+          else //if ((twain.m_linuxdsm == TWAIN.LinuxDsm.Unknown) || (twain.m_linuxdsm == TWAIN.LinuxDsm.IsLatestDsm))
+          {
+            twrange.ItemType = itemType;
+            twrange.MinValue = Convert.ToUInt32(value.MinValue);
+            twrange.MaxValue = Convert.ToUInt32(value.MaxValue);
+            twrange.StepSize = Convert.ToUInt32(value.StepSize);
+            twrange.DefaultValue = Convert.ToUInt32(value.DefaultValue);
+            twrange.CurrentValue = Convert.ToUInt32(value.CurrentValue);
+            Marshal.StructureToPtr(twrange, lockedPtr, false);
+          }
+          //else
+          //{
+          //  twrangelinux64.ItemType = itemType;
+          //  twrangelinux64.MinValue = Convert.ToUInt32(value.MinValue);
+          //  twrangelinux64.MaxValue = Convert.ToUInt32(value.MaxValue);
+          //  twrangelinux64.StepSize = Convert.ToUInt32(value.StepSize);
+          //  twrangelinux64.DefaultValue = Convert.ToUInt32(value.DefaultValue);
+          //  twrangelinux64.CurrentValue = Convert.ToUInt32(value.CurrentValue);
+          //  Marshal.StructureToPtr(twrangelinux64, lockedPtr, false);
+          //}
+          break;
+        case TWTY.FIX32:
+          double min = Convert.ToDouble(value.MinValue);
+          double max = Convert.ToDouble(value.MaxValue);
+          double step = Convert.ToDouble(value.StepSize);
+          double def = Convert.ToDouble(value.DefaultValue);
+          double current = Convert.ToDouble(value.CurrentValue);
+          if (TwainPlatform.IsMacOSX)
+          {
+            TW_RANGE_FIX32_MACOSX twrangefix32macosx = default;
+            twrangefix32macosx.ItemType = (uint)itemType;
+            twrangefix32macosx.MinValue = new TW_FIX32(min);
+            twrangefix32macosx.MaxValue = new TW_FIX32(max);
+            twrangefix32macosx.StepSize = new TW_FIX32(step);
+            twrangefix32macosx.DefaultValue = new TW_FIX32(def);
+            twrangefix32macosx.CurrentValue = new TW_FIX32(current);
+            Marshal.StructureToPtr(twrangefix32macosx, lockedPtr, false);
+          }
+          else
+          {
+            TW_RANGE_FIX32 twrangefix32 = default;
+            twrangefix32.ItemType = itemType;
+            twrangefix32.MinValue = new TW_FIX32(min);
+            twrangefix32.MaxValue = new TW_FIX32(max);
+            twrangefix32.StepSize = new TW_FIX32(step);
+            twrangefix32.DefaultValue = new TW_FIX32(def);
+            twrangefix32.CurrentValue = new TW_FIX32(current);
+            Marshal.StructureToPtr(twrangefix32, lockedPtr, false);
+          }
+          break;
+      }
+    }
+
+    static TWTY GetItemType<TValue>() where TValue : struct
+    {
+      var type = typeof(TValue);
+      if (type == typeof(TW_BOOL)) return TWTY.BOOL;
+      if (type == typeof(TW_FIX32)) return TWTY.FIX32;
+      if (type == typeof(TW_STR32)) return TWTY.STR32;
+      if (type == typeof(TW_STR64)) return TWTY.STR64;
+      if (type == typeof(TW_STR128)) return TWTY.STR128;
+      if (type == typeof(TW_STR255)) return TWTY.STR255;
+      if (type == typeof(TW_FRAME)) return TWTY.FRAME;
+
+      if (type.IsEnum)
+      {
+        type = type.GetEnumUnderlyingType();
+      }
+
+      if (type == typeof(ushort)) return TWTY.UINT16;
+      if (type == typeof(short)) return TWTY.INT16;
+      if (type == typeof(uint)) return TWTY.UINT32;
+      if (type == typeof(int)) return TWTY.INT32;
+      if (type == typeof(byte)) return TWTY.UINT8;
+      if (type == typeof(sbyte)) return TWTY.INT8;
+
+      throw new NotSupportedException($"{type.Name} is not supported for writing.");
+    }
+
+    /// <summary>
+    /// Writes single piece of value to the container pointer.
+    /// </summary>
+    /// <typeparam name="TValue"></typeparam>
+    /// <param name="intptr">A locked pointer to the container's data pointer. If data is array this is the 0th item.</param>
+    /// <param name="type">The twain type.</param>
+    /// <param name="value"></param>
+    /// <param name="itemIndex">Index of the item if pointer is array.</param>
+    static void WriteContainerData<TValue>(IntPtr intptr, TWTY type, TValue value, int itemIndex) where TValue : struct
+    {
+      switch (type)
+      {
+        default:
+          throw new NotSupportedException($"Unsupported item type {type} for writing.");
+        // TODO: for small types needs to fill whole int32 before writing?
+        case TWTY.INT8:
+          intptr += 1 * itemIndex;
+          //int intval = Convert.ToSByte(value);
+          //Marshal.StructureToPtr(intval, intptr, false);
+          Marshal.StructureToPtr(Convert.ToSByte(value), intptr, false);
+          break;
+        case TWTY.UINT8:
+          intptr += 1 * itemIndex;
+          //uint uintval = Convert.ToByte(value);
+          //Marshal.StructureToPtr(uintval, intptr, false);
+          Marshal.StructureToPtr(Convert.ToByte(value), intptr, false);
+          break;
+        case TWTY.INT16:
+          intptr += 2 * itemIndex;
+          //intval = Convert.ToInt16(value);
+          //Marshal.StructureToPtr(intval, intptr, false);
+          Marshal.StructureToPtr(Convert.ToInt16(value), intptr, false);
+          break;
+        case TWTY.BOOL:
+        case TWTY.UINT16:
+          intptr += 2 * itemIndex;
+          //uintval = Convert.ToUInt16(value);
+          //Marshal.StructureToPtr(uintval, intptr, false);
+          Marshal.StructureToPtr(Convert.ToUInt16(value), intptr, false);
+          break;
+        case TWTY.INT32:
+          intptr += 4 * itemIndex;
+          Marshal.StructureToPtr(Convert.ToInt32(value), intptr, false);
+          break;
+        case TWTY.UINT32:
+          intptr += 4 * itemIndex;
+          Marshal.StructureToPtr(Convert.ToUInt32(value), intptr, false);
+          break;
+        case TWTY.FIX32:
+          intptr += 4 * itemIndex;
+          Marshal.StructureToPtr(value, intptr, false);
+          break;
+        case TWTY.FRAME:
+          intptr += 16 * itemIndex;
+          Marshal.StructureToPtr(value, intptr, false);
+          break;
+        case TWTY.STR32:
+          intptr += TW_STR32.Size * itemIndex;
+          Marshal.StructureToPtr(value, intptr, false);
+          break;
+        case TWTY.STR64:
+          intptr += TW_STR64.Size * itemIndex;
+          Marshal.StructureToPtr(value, intptr, false);
+          break;
+        case TWTY.STR128:
+          intptr += TW_STR128.Size * itemIndex;
+          Marshal.StructureToPtr(value, intptr, false);
+          break;
+        case TWTY.STR255:
+          intptr += TW_STR255.Size * itemIndex;
+          Marshal.StructureToPtr(value, intptr, false);
+          break;
+      }
+    }
   }
 }
diff --git a/src/NTwain/TwainAppSession.Caps.cs b/src/NTwain/TwainAppSession.Caps.cs
index 0bb6227..1153509 100644
--- a/src/NTwain/TwainAppSession.Caps.cs
+++ b/src/NTwain/TwainAppSession.Caps.cs
@@ -1,6 +1,5 @@
 using NTwain.Data;
 using NTwain.Triplets;
-using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
@@ -268,6 +267,9 @@ namespace NTwain
 
     /// <summary>
     /// Sets a CAP's current value.
+    /// An easy way to create a value is to use the 
+    /// <see cref="ValueWriter.CreateOneValueCap{TValue}(CAP, IMemoryManager, TValue)"/>
+    /// extension method (or the other container variants).
     /// Memory of the value will be freed afterwards.
     /// </summary>
     /// <param name="value"></param>
@@ -287,6 +289,9 @@ namespace NTwain
 
     /// <summary>
     /// Sets a CAP's constraint values.
+    /// An easy way to create a value is to use the 
+    /// <see cref="ValueWriter.CreateOneValueCap{TValue}(CAP, IMemoryManager, TValue)"/>
+    /// extension method (or the other container variants).
     /// Memory of the value will be freed afterwards.
     /// </summary>
     /// <param name="value"></param>