I posted over on Reddit for help first, but ultimately the issue is unresolved. Anyone trying to help may want to look at the conversation I had over there.
I'm on Win7x64, Enterprise N. Ultimately, I'm trying to get my PC, connected to the internet with a 3G cellphone by USB, to share the internet connection with my router, which can then share it over the wireless. I've done this before, but I can't remember whatever I did to ultimately get it to work. However, I may be using a different NIC driver, and I am using a different Cellphone and a different driver for it. But the connection information and method is the same. (I also just attempted to use the old phone and driver, but nothing is appearing to be any different).
When I had it working before, I had the PC connected to the router's Modem port, but the person attempting to help me on Reddit says that shouldn't matter. He also recommended that I ignore the router for the time being, because ICS isn't set up right on my computer. Right now I have my PS3 in it's place, connected to my PC's NIC card with a non-crossover ethernet cable. (I don't have one, and didn't when I had this stuff working before... but that may be an issue...)
My understanding at the moment is that there should maybe be a drop down box on the Sharing tab for my internet connection's properties, but there isn't. There also isn't even a sharing tab on the LAN's properties.
I've easily spent 6+ hours on this yesterday (and now another 2 today, and I'm not even going to count past attempts to restore the setup where I just gave up.)
I'm willing to provide any information or screenshots I can. Any help would be greatly appreciated.