I have been playing it offline for a long time, but now I decided to try to play online. I am facing the same problem as the creator of this topic... When I create a game, the game gives a notification about my UDP port 4321. I have read many topics on the forum. Tried different combinations of my Firewall etc... Now I'm waiting for an answer from my internet provider as to whether I can open the ports. I tried to open ports through router settings, but on sites that check ports I still get the result that they are closed

When I enter online mode I can see other matches and I don't get errors, it only happens when I create my own game. But I was not able to join other players. I was getting a message that "player not responding" or that I have another mod installed.
Is there any way I can send to admins the Bug Report file? I don't understand at all how I can solve this problem....