Quicktime doesn't understand limewire?
 

Try to open limewire on mac, but quicktime doesn't understand... Help!

Download LW with Safari only. That's your problem. Explorer & sometimes netscape & some other browsers don't handle dmg files very well & you end up with incomplete dmg downlds. So the system doesn't know how to handle it. Go to your applications folder & look for safari & try again. Downld from here http://www.limewire.com/english/content/download.shtml