One thing I haven't seen mentioned here about mixing BiaB tracks; your Ultrapak also includes a DAW called Realband that has most of the BiaB features (including regenerating) and handles odd time signatures MUCH better than BiaB.
May want to take a peek at it.

It looks like BiaB interface as far a visual style (Old school), but offers many unique features.

I sometimes get the main song styles/tracks in BiaB, move to RB to flesh it out, and then to another DAW for finishing, although many times I just start in RB to begin with, since it has a more DAW like interface and most of the features.
A few of us here work like that.

They are still 'BiaB' tracks, just created in a different environment.
For me, the RB workflow was MUCH easier to learn and accept than BiaB, mainly due to preconceived workflows I was used to.

TBH, BiaB workflow still frustrates me at times, which is why, even when I use it, I move to RB pretty quickly.

I do not work here, but the benefits are still awesome
Make your sound your own!