Add 64bit tester and fixed version # in builds by switching to v6 sdk.

Build.cmd

@@ -1,3 +1,4 @@
 @echo off
 cls
 dotnet pack src\NTwain -c Release -o build
+pause

NTwain.sln

@@ -7,6 +7,7 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "_common", "_common", "{4CE0
 	ProjectSection(SolutionItems) = preProject
 		Build.cmd = Build.cmd
 		src\Directory.Build.props = src\Directory.Build.props
+		global.json = global.json
 		LICENSE.txt = LICENSE.txt
 		README.md = README.md
 	EndProjectSection
@@ -26,6 +27,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "NTwain-temp", "src\NTwain-t
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "WinForm32", "samples\WinForm32\WinForm32.csproj", "{7792A94E-D0B4-440D-8BD5-CA1CA548782C}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "WinForm64", "samples\WinForm64\WinForm64.csproj", "{C9666CB2-C9A6-48C8-AB51-D616A48058A7}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -43,12 +46,17 @@ Global
 		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Release|Any CPU.Build.0 = Release|Any CPU
+		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
 	EndGlobalSection
 	GlobalSection(NestedProjects) = preSolution
 		{7792A94E-D0B4-440D-8BD5-CA1CA548782C} = {707B4313-8EF8-4D0F-A95E-590783422187}
+		{C9666CB2-C9A6-48C8-AB51-D616A48058A7} = {707B4313-8EF8-4D0F-A95E-590783422187}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {7459323B-44F6-4E07-8574-E1B4B525086B}

global.json

@@ -0,0 +1,7 @@
+{
+  // have to use v6 since v7 doesn't generate correct version attributes
+  // for -windows variant
+  "sdk": {
+    "version": "6.0"
+  }
+}

samples/WinForm32/Form1.Designer.cs

@@ -1,4 +1,4 @@
-namespace WinForm32
+namespace WinFormSample
 {
   partial class Form1
   {

samples/WinForm32/Form1.cs

@@ -6,7 +6,7 @@ using System.Diagnostics;
 using System.Reflection;
 using System.Windows.Forms;
 
-namespace WinForm32
+namespace WinFormSample
 {
   public partial class Form1 : Form
   {
@@ -15,7 +15,9 @@ namespace WinForm32
     public Form1()
     {
       InitializeComponent();
-      Text += TwainPlatform.Is32bit ? " 32bit" : " 64bit";
+      var libVer = FileVersionInfo.GetVersionInfo(typeof(TwainAppSession).Assembly.Location).FileVersion;
+      Text += $"{(TwainPlatform.Is32bit ? " 32bit" : " 64bit")} on NTwain {libVer}";
+      
       TwainPlatform.PreferLegacyDSM = false;
 
       twain = new TwainAppSession(new WinformMarshaller(this), Assembly.GetExecutingAssembly().Location);

samples/WinForm32/Program.cs

@@ -1,7 +1,7 @@
 using System;
 using System.Windows.Forms;
 
-namespace WinForm32
+namespace WinFormSample
 {
   internal static class Program
   {

samples/WinForm32/WinForm32.csproj

@@ -6,10 +6,17 @@
 		<Nullable>enable</Nullable>
 		<UseWindowsForms>true</UseWindowsForms>
 		<PlatformTarget>x86</PlatformTarget>
+    <RootNamespace>WinFormSample</RootNamespace>
 	</PropertyGroup>
 
 	<ItemGroup>
 	  <ProjectReference Include="..\..\src\NTwain\NTwain.csproj" />
 	</ItemGroup>
 
+	<ItemGroup>
+	  <None Update="platforms\qwindows.dll">
+	    <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+	  </None>
+	</ItemGroup>
+
 </Project>

samples/WinForm64/WinForm64.csproj

@@ -0,0 +1,30 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>WinExe</OutputType>
+    <TargetFramework>net6.0-windows</TargetFramework>
+    <Nullable>enable</Nullable>
+    <UseWindowsForms>true</UseWindowsForms>
+    <PlatformTarget>x64</PlatformTarget>
+    <RootNamespace>WinFormSample</RootNamespace>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\src\NTwain\NTwain.csproj" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <Compile Include="..\WinForm32\**\*.cs" Exclude="..\WinForm32\**\obj\**;..\WinForm32\**\bin\**">
+      <Link>%(RecursiveDir)%(Filename)%(Extension)</Link>
+    </Compile>
+    <EmbeddedResource Include="..\WinForm32\**\*.resx" Exclude="..\WinForm32\**\obj\**;..\WinForm32\**\bin\**">
+      <Link>%(RecursiveDir)%(Filename)%(Extension)</Link>
+    </EmbeddedResource>
+  </ItemGroup>
+
+  <ItemGroup>
+    <None Update="platforms\qwindows.dll">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </None>
+  </ItemGroup>
+</Project>

src/Directory.Build.props

@@ -1,24 +1,24 @@
 <Project>
   <PropertyGroup>
-    <!--change in each release-->
+    <!--change these in each release-->
-    <PackageVersion>4.0.0-alpha.1</PackageVersion>
+    <VersionPrefix>4.0.0.0</VersionPrefix>
+    <VersionSuffix>alpha.1</VersionSuffix>
     
     <!--keep it the same until major # changes-->
     <AssemblyVersion>4.0.0.0</AssemblyVersion>
 
+    <!--even more unlikely to change-->
+    <FileVersion>$(VersionPrefix)</FileVersion>
     <PackageProjectUrl>https://github.com/soukoku/ntwain</PackageProjectUrl>
     <PackageTags>twain scan</PackageTags>
     <PackageLicenseExpression>MIT</PackageLicenseExpression>
     <PackageIcon>Scanner-Icon.png</PackageIcon>
-    <!--<PackageIconUrl>https://github.com/soukoku/ntwain/blob/master/Scanner-Icon.png?raw=true</PackageIconUrl>-->
     <RepositoryUrl>https://github.com/soukoku/ntwain</RepositoryUrl>
     <RepositoryType>GIT</RepositoryType>
     <NeutralLanguage>en-US</NeutralLanguage>
-    <!--<Copyright>Eugene Wang 2012</Copyright>-->
+    <Copyright>Eugene Wang 2012-2023</Copyright>
     <Authors>Eugene Wang</Authors>
 
-    <Version>$(PkgVersion)</Version>
-    <FileVersion>$(PkgVersion)</FileVersion>
     <LangVersion>11</LangVersion>
     <!--don't warn missing xml docs, naming conventions, and suppressions-->
     <NoWarn>1591,IDE1006,IDE0079</NoWarn>

src/NTwain/DSM/Readme.md

@@ -3,7 +3,7 @@ This is the lowest API level of the lib and should not
 be used directly unless you know what you're doing. 
 
 A higher level abstraction such as the ones in the
-`Triplets` namespace or the `TwainSession` object
+`Triplets` namespace or the `TwainAppSession` object
 would be easier to use.
 
 The individual classes are generated by the 

src/NTwain/TwainAppSession.Memory.cs

@@ -9,7 +9,7 @@ namespace NTwain
 
   partial class TwainAppSession : IMemoryManager
   {
-    internal TW_ENTRYPOINT_DELEGATES _entryPoint;
+    TW_ENTRYPOINT_DELEGATES _entryPoint;
 
     public IntPtr Alloc(uint size)
     {

src/NTwain/TwainAppSession.Windows.cs

@@ -72,11 +72,11 @@ namespace NTwain
 
     private bool CheckIfTwainMessage(IntPtr hWnd, int msg, IntPtr wParam, IntPtr lParam)
     {
-      // this handles the message from a typical WndProc message loop and check if it's from the TWAIN source.
+      // this handles the message from a typical WndProc message loop and checks if it's for the TWAIN source.
       bool handled = false;
       if (_state >= STATE.S5)
       {
-        var winMsg = new WIN_MESSAGE
+        WIN_MESSAGE winMsg = new()
         {
           hwnd = hWnd,
           message = (uint)msg,