Hi,
I’ve been annoyed with this for years. All of my games, of which most are Steam games, get blocked by the firewall, regardless if I add them as a trusted application or not.
Although I can connect to servers perfectly, I cannot host with either a listen or a dedicated server without turning off the firewall completely.
Any ideas on how to remedy this?
Maybe this will help you open a certain port for running a game server, it works for p2p programs and should also be able to work for game server hosting programs.
You can replace the mac address part with “any”.
Hope this helps.
Oh my god, you are a godsend!
After so many, in my opinion HORRIBLE, remakes of the UI, I couldn’t figure out where to do this!
No section made sense to me for straight up port forwarding! 
It works! Excellent! Thanks!
EDIT: Maybe that tiny guide should be edited and pinned as a guide on how to set up games/servers. I could not find any straight-forward info on this by simply searching and googling.
Glad to hear I could help!