Since I'm not sure what you have learned about BIAB, I don;t know if this will help but try this. First don't worry about a complete song.
The setup page for BIAB default is set for 32 bars 3 repeats, this is just to the right of the style name.
Start by putting in the total # of bars of the song, maybe 100 bars where the 32 is, then set the repeats to 1 where the 3 is.
Enter in the chords straight thru as if it's 1 long verse/chorus. Don't think about repeats, just place them in, where they come in in the song, each time you want those chords.
Hit play and those chords will play in the style that's in the style window.
Right click in the style window and several options will present themselves, one of which will be "browse styles" this will bring up the entire list of styles you have.
You might try starting with fewer chords, say a verse and try out styles to see what they sound like.
From your post I understand the frustration and what I have suggested , you may have already done.
Since you have been around computers awhile, I'm sure you understand the idea of a small test program to learn the more advanced features.
That's how I learned the small amt I have gained and much more from the forum members
Wyndham