I thank you all immensely for your very helpful replies. I've been confused by this topic a lot and didn't realise there were such underlying issues other than my own amateur working with the software.
Where I do have experience though, is software development. I know that BiaB’s beginnings were simply to accompany the artist, like it says "Band in a Box". But over the years the software has morphed further into DAW territory, for which it had no foundation. Trying modify software like this and still keep all the original features is a feat that most would shy away from.
I still think it is a fantastic product for its original purpose: The drag and drop feature has been the saviour for me. My workaround for this particular problem was to find the Midi track and drag it to Ableton, process it in Ableton if necessary and then bring it back on to Utility track.