If you think you got problems with the ports, try out hamachi or tunngle. Hamachi lets you create a personal local network (LAN) over the internet. If everyone joins that network you can just connect via direct ip connection, without the need to open ports. I already tried this and it works. Another method is tunngle, its essentially the same, except that you dont have personl networks, but community networks, where random strangers can join too. The game iteself didn't show in the LAN game tab, so its unlikely for someone to join if they dont specifically know that your hosting a game, but it mightve been just on our end that we could see each other games. But direct ip connection works fine.
