Oops sorry...
http://www.gnutellaforums.com/genera...der-vista.html
This is more than likely not going to help you with the Nat firewall...It can work with connction problems, but by the sounds of the trouble you have been having it's not the fix, but I could be wrong...
You might want to purchase a new modem/router, one that doesn't contain the Nat Firewall....