30 Jul 10, 12:41PM
I have done this many times. Follow the tutorial THESOUNDOFRAP gives you cause it is really great. However, in the beginning, for port forwarding, you need to be an admin on your Airport. Go to Airport Utility, select your Extreme, and click on Manual Setup. Enter your password, then go to Advanced>Port Mapping. Click the + button. In the window that pops up, don't enter a service, but add 28763, 28764 for all the public and private UDP/TCP boxes. In the IP address box, enter you IP by going to http://whatsmyip.org . Click Continue, then in the first box, enter AssaultCube. Click Done, then Update. Follow the rest of the tutorial and you are all set!