Jim,
"Every transport button tells Band-in-a-Box to perform one task."
Not really. You are forgetting the Play button.
Let's assume we get that option, how it will interact with Play button that does auto-regeneration as it "senses" changes in composition and regenerates all non frozen tracks automatically.
P.S. time to upgrade laptop? I keep an older PC for guests to browse internet, check email, etc. if they are staying over, but for music making, even for forgiving BIAB, i3/8ram is pretty weak.