Messing around with it, I tried using the LAN port, which didn't work at all. Then I put it back in the Internet port. Now, the online configurator required I call the registration number again. I did, and the subsequent web page required the obi unit's admin password. I gave it, and then everything fell into place. I have no idea what happened. I didn't give a password before, but how could I have passed that screen without it?
It's working, but I'm still confused.