This just goes to show you how Limewire, heck just about any program in the world, can have very very varying performances depending on configurations.
Anyhoo, looks like you're in for a little reading (if you haven't already done that. The following threads are for increasing dld success (for the first one) and dld speeds (for the second):
-
http://www.gnutellaforums.com/showth...threadid=17321
-
http://www.gnutellaforums.com/showth...threadid=27036
I think that Lord of the Rings has already pointed you to these stickies, but oh well...