Evaluating third party tools for 64-bit compatability

Hi.

I hope this is a reasonable forum to choose.

Desktop WinForms application, C#, Framework 4.0, Visual Studio 2010 SP1.

I'm evaluating migrating an app to 64-bit.  I've read what I could, then figured I'd try a test before contacting any vendor: create a new project with one form, add their control to the form, build for x64 (cross-dev), then copy the binaries to a 64-bit system and try a launch.

The third party tools are assemblies, which also target Framework 4.0

First question: what should I expect to see in dependency walker (depends22x64)?  What I do see is that the dll file for each third-party component shows as 32 bit.

In the testing, two of the components loaded, while a third caused an error like this:

Application: WinForms64BitTestC1andTList.exe
Framework Version: v4.0.30319
Description: The process was terminated due to an unhandled exception.
Exception Info: System.BadImageFormatException
Stack:
   at WinForms64BitTest.Form1.InitializeComponent()
   at WinForms64BitTest.Form1..ctor()
   at WinForms64BitTest.Program.Main()

Now, the norm in .NET is that, through the CLR, an application or component can run either way?  Is that right?  Is the 32-bit designation in Depends a counter-indication?  The application (exe) itself shows as 64-bit in Depends.

Thanks!

Art

---

Arthur Gardner