[Scenario]

You may need to set up a static IP address for your computer, as well. As for the link above, it should be simple enough for you to follow and understand. Make sure that in your server.cfg file, you have the port set to 7777 and nothing else. You'll need to make sure that you pointed that port to your computer's internal IP address as well. If you don't already know, you can go into Start > All Programs > Applications > Command Prompt and then once the command prompt opens, type in "ipconfig" and look at your Local Area Network Connection.