With the newest release the demo program pops up, and everything other than the image is work, led, motor, accelerometer. I tried downloading visual C# 2010 and compiling it from source but ended up having a XAML parsing error if that helps.
i ran into the same trouble. the xaml error was caused by a wrong dll version. since V1210 doesn’t give me any cam pictures under xp i switched back to V1121 after i (thoght i) uninstalled everything. the CLNUIDevice.dll V1210 was still present under c:\program files\code labs\... and did not get overwritten by the installation routine of V1121. so it’s actually not xaml mark up errors but null pointer exceptions caused by calls to the wrong dll (camera = CLNUIDevice.CreateCamera(); does not return a valid pointer).
i also deleted the windrvr6.sys in win/system32/drivers as well as the CLDevices.dll prior to installation (though that might be unnecessary).
now everything works like charm and way faster than the libfreenect / libusb stuff i have to say.
cheers,
TiM