I'm not an expert with routers or wireless connections.

But with a router, the PC Operating System itself, and (possibly?) the D-link wireless, you could have 3 sets of firewalls for the connection to navigate through.

So I would investigate the firewalls of each first; eg what firewall does the PC have? Is it blocking the connection to the game?

What about the router firewall? Is that what you mean by a NAT? If so, then you probably know more than me.

What about the wireless encryption safeguards?

As you say that it is not up to you about the routers, are you an Adminitrator on this machine? If not, then you need to contact/speak to the Administrator.

Like I said, not much help.

But if I need your maths skills, I will be round like a flash! Happy