Bob:

I went back to my 2014 BIAB and tried this.
It seems to work fine although I'm not sure exactly how you want it to sound.

What I did was, open a "new" blank chord sheet, and put one chord in each of the first 4 bars (C, F, G7, C), then set the # of choruses to 1, the "end" bar to 4 and unchecked the "Generate 2 bar ending".

You may also want to take out the "count in" unless you need it to get ready to play in the next random key.

Then I set the Transpose Song to Random (the same as you did).
Now when I hit Play, it changes to a new key for every "chorus", i.e. everytime it plays 4 bars.

You might try that first and see if you can get it to work, then go back to your original original song and see what's different.

Good Luck!
LLOYD S