Well sure, if you just leave LW open and don't check up on it then don't expect your dlds to be done quickly.
As someone said in a post before (I think it was ursula), LW likes to be "baybissited", meaning that whenever you get Awaiting Sources, it doesn't mean that LW is automatically searching for sources.
Now, don't take this the wrong way and start bombing the network with continuous searches over the same file 'cause that results in the slowing down of the network.
Just run a search and then, after some time repeat the search. (doing the search over and over but in rapid succession will only get you the same sources wich didn't permit you to finish your download anyway so wait before repeating them

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iMac G4 OSX 10.3.9
RAM 256MB
LW 4.10.5 Basic
ADSL anything from 3 to 8Mbps/around 1024kbps

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