I programmed mine through the serial port and found mine the same way as you did.

I swear when I first picked it up, I tried to get into it and couldn't due to a password. It sat on a shelf for close to 2 years and I decided to try again and got in. I don't know if it lost the password after all that time or if I am just crazy but either way, I have searched all over the place for a way to default them and have come up empty so far.

I've lost the link I had how to use the dip switches but they are also programmable by the dip switches on the main card by default. If it wasn't disabled via the serial port you might have a chance of making it work.

The other option depending on how you plan to use it, is to use the settings it is already programmed with. If it just has FXS ports, then the configuration is pretty simple and could probably be made to work as is.