I just ordered my router from T-Mobile. I'm hoping I don't have any issues like you have. My internet provider is COX (Broadband Cable) and I also already use a wireless router. I don't download a lot of stuff, but my son plays on-line video intensive games, so I'm hoping that won't be a problem. I can access upto 3 seperate IP addresses and I have a switch, but don't know if that would help because it all goes through the same modem. I stopped using the switch some time ago though, as I don't need a second or third IP.
Guess we'll see how it goes, but I'm pretty pumped knowing that I'm going to save at least $30 a month in phone bills.