be sure hashing process is finished, then disconnect. open process viewer in -applications-utilities, check cpu usage for limewire.
I say that cause every 2.6.x is a cpu hog on my machine even when idle. It takes 20-30% idle compared to 0-12% for Limewire 2.5 uploading and downloading on my iMac. Report your cpu usage here, cause Limewire should work out this problem if generalized in X.2.

Thanks