I've never liked how the CLF node's library path attribute worked. Yes it is tricky. I am not sure why you are having problems just specifying the name of the dll. This should work, and I don't know of any other "hidden" settings that will make it work. Also, there are some other things with CLF that you might find useful:
You can specify the library name as "YourLibName.*" instead of the platform specific endings of YourLibName.dll (Win) or YourLibName.so (Unix/Linux), YourLibName.shlb (Mac OS 9), or YourLibName.framework (Mac OS X). This allows you to include, in your distributable code, the shared libraries for all platforms and LabVIEW will choose the right one for the target platform.
You can also put the DLL in the root direct
ory of LabVIEW, or your built application and it will be found at load-time.
-Jim
PS - If you attach a copy, I'll see if it can load on my machine.