I use Limewire for quite a time know under OS 9 and never had (major) problems.
Today I downloaded it for OS X, set it up and entered a search string. The results came as usua,l but when trieing to download any file I got the message "Could not move to library"
I tried changing the shared folders to different volumes, different foldernames, with and without shared files, but no luck.
Then I tried to open my old limewire in classic modus, but guess what? SAME ERROR!
Troubles with permissions under OS X perhaps?
So reboot in OS 9.2.
again: SAME ERROR!!

Conclusion:
I don't know what's wrong