Port 6346 is the one I have configured for Furi and since I am using NAT as well I've typed in my 'real' IP above that port number so people can connect to me and get my files. So, open that port and redirect it to your NAT client IP address inside your firewall. The last thing to do is type one of the following in the middle of your Gnutella Network screen to get some valid hosts to connect to.

gnutella.hostscache.com:6346
gnutellahosts.com:6346
router.limewire.com:6346