I had the same problem when I first got my Cinema7. What solved it was carefully rethinking how I would use the Cinema. By only copying critical commands (instead of every command from the original remote) I could control my devices 95% of the time. That 5% when I needed other commands it was simple enough to get out the original remote(s).

I don't own a TIVO (yet) but know it's not natively in the Cinema7. Learn memory is extremely limited, so the above suggestion to "upgrade" the remote may be your only option. I doubt anyone does this commercially yet (you send in your remote and they upgrade it for you) it is probably worth doing yourself. Otherwise you'll need a Pronto or other much more expensive remote to handle all your equipment.

Good luck,

Dave