(Just in response to the last few posts.)
It is my understanding the Resume button was designed to attempt to connect to the original sources. And that the Find Sources button was designed to try to re-connect to files that had been downlding earlier in that same session.
However it's my belief (right/wrong) that too many people have an easy plug & play attitude where they just want to open LW & resume all their files & runaway & play another game. I believe that's abusing the abilities of LW. It puts a lot of pressure on LW, the computer's resources, & also the connection, & probably also the Gnutella network with too much simultaneous/constant traffic. On the forum people wonder why their computers freeze or lose connection, or get poor results.
I find Resume is best used when a file has been previously downlding that session but stopped or else, the search results are still present & valid. Or the function is used well after LW has settled down & attempted to make its own connections with all incomplete files. Then choosing to resume individual files. Well that's my experience & IMHO.
A search for the topic is the best way to find sources IMO. So LW sometimes needs some baby-sitting. Just letting LW look after itself seems to work for me most times. Perhaps b/c I very quickly seem to have people uploading from me - and I have a variety of shared material.