I am unable to ADD my Frontlines: Fuel of War server into GT running via Tunngle.net service

It always says it can be firewalled, but I am able to query this server from anywhere else

IP: 7.48.29.201
Join port: 20013
Query Port: 20020

I have confirmed that 7.48.29.201:20013:20020 cannot be scanned on HLSW.

You may find this thread useful http://www.gametracker.com/forums/forum.php?site=1&thread=74094#cfrmpsts

Additionally, since you indicated you set it up as a LAN server http://www.gametracker.com/games/ffow/forum.php?post=312215#post312205 , There may be issues querying from an external environment.

I forgot to add that Tunngle software must be running with an account linked to the unique private network, so its impossible then for gametracker to query such server, too bad.