one of the reasons why many downloads don't finish any more is because after limewire 2.8.x the automatic requeries that would re-search for a file after a certain time to find more sources were removed.

this means: if you're downloading from, say, 3 hosts, and all these three users disconnect before you're done downloading, limewire won't try to find other hosts serving the same file, i guess it will just stop.

however, you can manually re-search for the same file and if limewire finds any new hosts, it will add them to the download queue.

this is a bit more work for users, but apparently the automated re-queries were an enormous waste of bandwidth.