i went and added the empeg in HyperTerminal, but nothing displays when it boots up.

Right, so there's something wrong with the serial connection. That's why the upgrade doesn't work. Go through the text in the Hyperterminal FAQ entry and read each paragraph carefully and do all of the troubleshooting. If Hypterterminal doesn't work, then the upgrade won't work. If Hypterterminal works, then the upgrade should work.