We use Tunngle to set up the games.

When I host a LAN game, and players connect to the game lobby, my game freezes. It unfreezes when they disconenct.
When I connect to another player's lobby, the game freezes when we are in the loading screen. Their game freezes too, until I disconnect.

I have this issue only with Tunngle. The other players are not affected. This issue did not come up when we used Evolve for setting up the lan.

Does anyone know what the problem might be? Does anyone have an alternative vLAN tool?

Have you tried manually opening the ports required? As a test you can try completely disabling your hardware firewall for a short time just to see if that is the problem.

Have you tried to the old trusted favourite Hamachi?

Thank you for replying.

Yes, I have forwarded my ports and disabled my firewall.

When using hamachi, we can't see eachother in the lobby.