I had a chance to play a lil bit with BT and didn't have any problems, which leads me to believe that your router isn't configured properly. You shouldn't have to do any special changes to your router, since the connection originates from within your LAN, and a properly configured router will automagically allow replying packets back through (unless the prot:port is blocked specifically, like for the Blaster worm or some such.)
If you're wanting to check your outside IP, you could use
this address. (and yes, anything 192.168. is non-routable. I forget the RFC, but yes, you're correct :)
Try resetting your router back to it's factory settings (or just remove all port forwarding settings) and try it again. I've never used that router, but I know for me to use BT, I had to make 0 configuration changes on mine.
Let me know how you make out.