Hi there, i'm not an experienced user at all but i had the problem of limewire loading and opening with a blank screen and while searching would have blank search tabs. Not sure if this is the same problem you're having but it might just work! Try this (it worked for me) - Change skin modes. I changed my skin mode from their default one to the metal skin and everything came up fine. All other skin modes still came up with glitches except the Metal skin. In regards to files showing many sources but not being able to download, i've read that its because they're fake files. There's a thread posted by member "Lord of the Rings" explaining the situation with that.
Hope this helps