I don't have U-Verse but I'm thinking you should be able to switch their equipment to a 'pass through/bridge' mode to where it should just act like a modem at which point it should just pass traffic ...

I tried to setup port forwarding on my TrendNet TEW-432BRP router recently and I cannot get it working for my FTP server or my SSH (both to a Linux box). This is a new house, new internet connection ...