How can I forward a port when using PdaNet?

I'm using PdaNet to connect my laptop to the Internet. From there I'm using an ethernet cable and Internet conection sharing to connect my PS3 for online gaming. Works pretty good for most games, but one in particular will not connect to the server. I need to know how to adjust the router settings when (I think) the phone is the router. In particular, how can I forward ports and enable UPnP? If this isn't possible, is there another setup i could use to get what I want? I've got my laptop running Win7 64 bit, a Belkin Play N600 router (not used currently), a stock LG axis AS 740 Android phone (2.1 OS) and the PS3. Oh, and the game I'm trying to play is Modern Warfare 3. I'm just not very tech savvy.