Oh, well, Advanced Library can convert RSRs, too. (Just so every app is mentioned here...)
And it allows me to find Poser content since years and is better than anything I've ever tried (maybe because I made it the way I need it? ;-))... Oh and it loads content into Poser 8 the same way the library interface does it..End of Advertisement.

But maybe back to the problem: Can you post the full path to an item that's not working?