Ya agreed. I never let my cats or kid play with things that can easily kill them.

Underrated comment. Well executed.

I agree with the double nat on the adsl side. If you have a private IP and still have internet it’s behind a NAT. You need a public IP on the top right. When you say forward traffic what type of traffic is being sent? Do you want it relayed or are you ingesting it and manipulating it in some way? I guess what is the server in top left doing with it before it goes to game server at top right? A simple route would pass this traffic from server to game server at the routing level.

Can you draw a diagram? It kind of sounds like you need either NAT or VPN or a combination of the two.