LW does not use a central server! It's simply connecting to the net & to other peers. People like yourself.
Did you configure your firewall so it allows LW full access (advisable not to have 2 active firewalls b/c they can interfere with each other);
Firewall configuration instructions (click on link)
Do this simple test for us. Using your browser go here:
http://www3.limewire.com:6346/ The page should say 'Your test worked!'. What happens when you go there?
I've seen these tests listed multiple times around the forum. If you look you can find believe me!