When you choose a shared diretory, it needs to be able to write to that directory. It ALSO creates other directorys named Incomplete and .limewire within the same directory level as the shared directory. The program needs to be able to write to all of these directorys.

During installation, Limewire chooses a default directory within the same directory level as where the program was installed. I suggest changing the shared directory folder to one within your home directory. i.e. choose the directory
/home/user/shared
where "user" is the individual home account name. It will also create /home/user/incomplete
and
/home/user/.limewire

FYI: You can also install limewire, program and all, entirely within your home directory.

Hope this helps.