my half-educated guess is that the source of the problem is event handling
in some cases it doesn't work as documented, which may disable certain range checks etc
I didn't cross check it on Win7 yet
(currently using VS2010 express, but will do when the full version arrives)
basically the .Net stuff runs ok, but I had to implement workarounds for a couple of items
for the curious ones who are code savy, here's the most minimal example that fails on my system:
(I'm not the author)

http://www.codeproject.com/Articles/464 ... WPF-events
(middle of the page)
it's just a standard button/mouse/keyboard event handler with a single line of code
in my case it eats up the event, though the functions are supposed to pass it
with an extra line of code to manually raise the event on exit it works as should be...
as Win XP isn't supported anywhere officially, a switch to Win7 and above may apply...
cheers, Tom