Not sure about setting it up from the front panel but Harmony remotes have the hts 7.1 in their database. Should be able to set one up to do all the commands.
check e-bay, these remotes aren't that difficult to find. They are small plastic wafer remotes.
If you can't find one, I have a big heavy metal Krell remote from an Audio Video Standard, but I don't know if that would even work.
I need to keep my HTS 7.1 remote. Finding a learning remote would be easy and getting somebody to program the volume only would be a piece of cake. You have a dealer you can borrow a remote from?