Sorry guys, about the lack of details. I use a Roland 2400 Digital recorder it has 24 tracks so that's not a problem. I always record each instrument to a separate track.

Could you describe, IN DETAIL, what your routing looks like:
MIDI out from my PC to Sample players (Roland U110 and Kork P3) and several analog synths. Outputs from all of these go to the Roland 2400. Drums on the 1st 4 tracks and then each instrument on it's own track. I then add acoustic instruments and vocals with a mic right into the Roland 2400. I want to record the Real Tracks instruments along with all of the others each RT on it's own track.

I hope that I gave you a clearer picture of what I'm trying to do. Please let me know if you need any other info. Thanks!