I think what you are seeing are fake files as they never connect and you will always get the need more sources message...
This link will explain how to avoid them, it also explains how to use Bitzi (a real life saver)...
http://www.gnutellaforums.com/downlo...h-results.html
Now with your firewall, you said you Port Forwarded did you follow these instructions when you did...Also did you apply the same number in the manual port forward box as well as the listen port box ??
Port Forwarding for the Trendnet TEW-432BRP