Just click on my name and use the email address in my profile. You can send a Biab file as an attachment. As to the forum timing out, just refresh the screen before you send a long post, that usually works. If it doesn't then do a ctl c and copy it just in case you lose it so you can do a new post and paste it back in.
Creating a stereo audio file is the easiest and safest way to do this but as you said, you lose control of individual tracks. You can do say 3 versions of each song and name them ...full, ...-drums....-guitar or whatever but Biab and RB will do what you want, we just have to get you going on how it works. You seem to have enough resources to get what you need within reason. I'm thinking a purchase of the Ketron SD2 could be just the ticket for you. The sounds are quite comparable to the Real Tracks, everything stays in midi so it's instant loading of each song, no freezing or Conductor problems or anything else. Anyway, send me a Biab song and we'll see what's up with it.

Bob

Biab/RB latest build, Win 11 Pro, Ryzen 5 5600 G, 512 Gig SSD, 16 Gigs Ram, Steinberg UR22 MkII, Roland Sonic Cell, Kurzweil PC3, Hammond SK1, Korg PA3XPro, Garritan JABB, Hypercanvas, Sampletank 3, more.