I think my firewall was off, and then I put a tick in the box "iTunes Music Sharing" and then it said that it was on. Then I followed the instructions that you gave me, then started limewire and it still didn't work.
Now, I've just tried to download one of the magnet video files and after being queued for a second or two it worked!! It is downloading from 3 hosts at 187 KB/s. I tried a magnet music file again, and immediately it said that it needed more sources. Maybe the problem is only when downloading music? Also the green bars at the bottom LW are always all green, with a very strong connection. I am connected through an apple modem.