Sometimes the way the source gets interpreted is changed.
So some of your chord sheets might not work as expected anymore.
You have to go through all your chord sheets and fix them manually.
Sorry, but that's just the way it is.
Before, it was accidentally possible to write slash chords with lowercase letter bass note.
The resulting chords looked very ugly, and that was false anyway.
Now you have to write slash chords always with an uppercase letter bass note.
Before, all diminished chords were rendered as diminished seventh chords.
There was a user setting to toggle between dim and dim7 chords.
Well, that was slightly wrong, as these are different chords.
Now you have to write e.g. Bbdim or Bbdim7 in your chart.
The user setting just determines if the diminished chord is rendered as literally dim or with a circle symbol.
If you use diminished chords in your songs you have to check if it still is the desired type. Just Dim or Dim7.