@Noel and Matt. Thanks for suggestions and looking into it.

The Cb and E# thing makes sense to me, too. Even if, for the sake of using chord scales, Cb or E# would make sense. I know really good readers, like those working professional classical orchestras have no trouble reading double flats or sharps on top of -say- a key signature of Ab, but, for the ordinary musician, reading is already hard. And an F is an F and E# is is F. So, I dig that feature. Professional classical players will turn to Finale and Sibelius anyway.

To look up the history of it is a clever idea. Since 2022 has a lot of issues with midi style making or editing, I still use 2018 a lot. So, to my surprise, the Bb was written as a Bb and not A#. The wrong note in the example above (C# instead of Db, since we’re in a F, a key with one flat) was still there.

When I corrected it in editable notation in BB2018, it survived hitting play AND even closing Biab2018 and reopening it.. BB2018 has other issues, so I am not using it for practice let alone performance, but it handles forcing accidentals just fine.

So, there must be a mistake in saving forced accidentals that crept in after version 2018.

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