Drum part munged after using Staff Properties dialog

Seen on OS X Mavericks, latest nightly build.

Main problem:

* Open attached score
* File | Parts | New all | Ok
* Look at the Drums part. It's ok, except that beamed stems have default direction rather than the intended direction (issue already reported). Oh, and the instrument name is at the top left corner of the text box when it should probably be bottom left.
* Still in the Drums part, right-click the staff and open the Staff Properties dialog. Then close it without changing anything.
* A few things have now gone wrong. It's a single-line staff rather than a 5 line staff, and the staff, instrument name, clef and surviving bar line have moved up 2 spaces relative to the notes and time signature (which appear to be in their original location).

Bonus problem:

* Now Undo.
* This is almost where we started from, but the bar lines extend for one extra space above and below the staff.

The Drumset line in the score remains the same throughout. These issues only affect the part.