I've been working on figuring out the behaviour of SHQueryValueEx using XP for testing. I know that on XP SHQueryValueEx just calls SHRegGetValue, so any results from testing SHQueryValueEx match those documented about SHRegGetValue and even those not documented. What I'm wondering is if SHQueryValueEx behaves the same on other platforms ie 95/98/NT etc. If you'd like to test it, run the attached test on your platform and report the results back. Thankyou for taking the time to help figure this one out. BTW you can ignore this error for now (I'll look into it after this):
shreg.c:270: Test failed: didn't open copy