[Mac] Creating score with linked tablature staff causes corruption

1. 'New…'.
2. At the instrument step, add the top 'Acoustic Guitar (nylon)'.
3. Click on stave.
4. 'Add Linked Stave'.
5. Change staff type to 'Tab. 6-str full'.
6. 'Finish'.

Result: One, or more bars appear with a crotchet.

Note: It can't always be reproduced. It seems to be exclusive to Mac. It happens in random bar(s) and the actual duration of them is 4/4. The rests can sometimes be divided and not be corrupt. See screencast .

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7. Select rest.
8. Change to quaver.
9. Change to crotchet.
10. 'Undo'.

Result: The bars has no rests in either stave.

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7. Select crotchet rest.
8. Change to quaver.
9 Change to crotchet.
10. Change to semiquaver.

Result: Both staves have different amounts of rests. The pitched stave has the following: a quaver, semiquaver, quaver, crotchet and minim. The tablature stave has the following: two semiquavers, a quaver, crotchet and minim.

Note: Not always reproducible.

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7. Select rest.
8. Change to quaver.

Result: Both staves have different amounts of rests. The pitched stave has two quavers, a crotchet and minim. The tablature stave has a quaver, two crotchets and minim.

Note: Not always reproducible.

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7. Select crotchet rest.
8. Change to quaver.
9. Change to crotchet.

Result: Three and a half beats.

Note: 'Undo', then 'Redo' seems to correct it, until you do steps 7-9 again.

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9. 'Undo'.
10. Change to quaver.

Result: Crash.

Note: See attached log.

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Note: There maybe more corruptions involving Undo/Redo and changing values.

Using MuseScore 2.0 Nightly Build (55c5791) - Mac 10.7.5.