Port Forwarding Issues

I've got a 2wire 3800HGV-B Gateway, used with AT&T's U-Verse service. There are a couple of ports I've tried forwarding (using a process similar to this), but for some reason none of the ports are actually open, as determined by sites like yougetsignal. It's perplexing to me because these ports were in fact open previously, yet for some reason they're closed now. Also: I've got port 47850 open for use with uTorrent. Yougetsignal tells me this port is closed, but the instant I actually open uTorrent the port becomes open. Wha?

Locally I only have Windows Firewall running, but exceptions to the programs whose ports I want forwarded have been set up the wazoo. Disabling Windows Firewall didn't seem to have any effect on the ports, so I don't believe that's the problem.

Anybody have any suggestions? This whole thing is really pretty frustrating. I can provide screenshots or whatever so you can ensure that I'm doing the whole thing properly.

Jam it back in, in the dark.

When Utorrent the port is closed because of a service called uPNP. This calls your router to open the port ONLY when the port is needed (opening Utorrent). Why do you want a port opened 24/7? Or am I understanding this wrong?

There's nowhere I can't reach.

uTorrent was just an example. I'm not actually too concerned about that specifically.

I don't necessarily want a port open 24/7. I play this game that has netplay enabled, and I need to have port 10800 open to allow other people to connect to me. As stated in the topic post I've already gone through the process of forwarding the port in the router, but the port doesn't appear to actually be open. It's closed regardless of whether or not I have the game (which is set as an exception in Windows Firewall) open and running or not.

This is all very frustrating primarily because ports were forwarded properly not but a week ago.

This thing is sticky, and I don't like it. I don't appreciate it.