Hi
Sounds like you're using the rights APIs, all right. I've tried them all the way up to 6.2 and they look ok.
Your other option, which is what we were doing before AcuCorp provided the wrappers, is write a C/C++ DLL that does the job for you...
Also, I think you might need admin rights for the LOCAL_MACHINE branch. Without them, you might be able to open a node (or at least the wrapper API says you just did so), but may not be able to access the data.
.DaviD.