Allowing directx games access

Need some help with said topic. I have a NAT router which is configured with directx ports open. I don’t use network control rules in Comodo, just Application rules.

Anyway, I’ve been trying to play Motocross Madness 2 with a mate on a direct tcp connection. If Comodo is set to allow all access it works fine. But when I set it to custom security, MCM2 hangs when trying to start a multiplayer game. I have added the game’s executables to the application rules - both MCM2.exe and MCM2.icd. Is there anything else I have to add to get this to work? The logs are empty as like I said network rules are switched off. What else can I try?