lambada,
This would be better in it's own thread in BIAB (Windows). I anticipate that there will be more responses regarding this as it's probably easily not seen here.
I'll have to do some homework on what you're describing but I always thought that midi tracks are controlled by the Stylemaker and cannot be simply added and subtracted like Realtracks can be. (If I'm correctly understanding your issue.)
Regards,
Noel