You are absolutely right about the unit code being part of the IR signal. UEI doesn't have any codes with anything other than unit code zero for TiVo, so your only option to get the remote properly programmed is via JP1. (Note, as the Kameleon is upgradeable using WAV files, you might not need to actually build a JP1 cable as there is a program now that will generate the WAV file for you. I don't know much about this program yet, so you'll need to ask in the JP1 group)
Rob
[Link: hifi-remote.com]