Grace notes incorrectly presented upon change, or undo of it

1. Open attached score (produced in 1.3).

2. Click on grace note, or its beam.
3. 'Flip'.
4. Double-click beam.
5. Drag either handle.
6. Click elsewhere (leaving edit mode).

Result: The grace notes are incorrectly positioned.

OR:

2. Click on bar (selecting it).
3. Move an octave down (Command and Down).
4. Double-click beam.
5. Drag either handle.
6. Click elsewhere (leaving edit mode).
7. 'Undo' twice.

Result: The grace notes are incorrectly positioned and have long stems.

Note: It is also reproducible in a 2.0 score.

Using MuseScore 2.0 Nightly Build 911328c - Mac 10.7.5.