When registering the NAS-2.3, how do I get it to use my broadband connection instead of the internal modem?
Select "Register Later" if prompted at startup and then "Register Now" once the main menu appears. It will say it's using you dialup account, but since you've specified Ethernet it will actually use this instead. When the registration is successful you will get a confirmation window. Once the server successfully registers, the Register option will disappear from the main menu.