Flexibones Bezier handles unwanted corners after Update

After an automatic update, the Bezier handles of flexibones no longer work as before.
All my old files look distorted. I read that the programming was changed. However,
when I create a new animation, for example, a simple arm with three points,
and drag the handlers, unwanted corners immediately appear where
there were previously elegant curves. Is this a bug, or do I need to
work completely differently?
I installed an older version and it works again. However, I'm afraid that these older versions will eventually no longer be available.

Unfortunately, this affects not only me but also my students, as I work as a lecturer.