You made a listen server and listen servers can only be joined by people who know your IP address. You need the dedicated server function on if you want your address to be broadcasted to master lists. Also when you make a dedicated server it is supposed to minimize and the box thing is there. That is the computer making the server for people to join. A good server will just have teh computer running the game because it takes a lot of memory and other computer thingies to connect approx 2-32 players. You should be able to join your game that is running dedicated on your computer by bringing up JK again.
If you want to be able to customize your server better search for something called Jedi Runner. Nice program.
There could also be the problem of a firewall and people not being able to connect.