OK, I couldn't sleep anyway, so I got busy with your instructions, Larry. :P
I used BIAB to produce a midi track which I then loaded into Reaper. It was a chordal track that I hoped would work... otherwise I would go back and do as you suggested and just use a single note track.
I did the track selection in the Digitech first and set it for "omni". I set the system channel to 2 also.
Then in Reaper I did everything as you suggested (this was where most of my confusion came from...), played the track, and EUREKA! I now have my MIDI input to the Digitech! I sang into the mic to make sure I got harmonies, and, on those infrequent occasions I was on key, it worked great!
Thank you so much, Larry the Guru!

You're expertise is very much appreciated!
Jim