I am not on the computer that has the problem or network, but I'll edit this when I have the ports and router model available. I'll just say it's a Belkin.
I have set up ports for different games, Garry's Mod, Terraria, Minecraft, TF2, and CS:S (Garry's Mod ports have all of TF2 and CS:S's ports taken care of).
However, I have 2 problems: One with hosting, and one with the router itself.
I'll talk about the router first: It's really really buggy. When I tried adding a 6th port, it gave me a error. Tried changing it, still the same thing. When I exited and went back, it copied a entire port setting to EVERY EMPTY BOX THAT WASN'T 1-5. I deleted it, but that's really, really annoying. Why do I have this kind of buggy thing? However this was before a firmware update, so this may have changed.
And the hosting problem: I set up the ports, and tried hosting a CS:S SRCDS server with the setting -ip 192.168.2.7 in my shortcut. However, it errored out with "Couldn't allocate any server port" and exited. I tried Bukkit, tried joining, wouldn't connect to my public IP. Tried Terraria, and still nothing.
What am I doing wrong? I set the private IP's area to 192.168.2.7 in the router settings, and the port ranges were right, and I set all of them to TCP/UCP.
I will update this when I get back onto my network and get back to my house, as I am at someone else's house right now.