Checking post permissions

(First-time submitter. Did not find this issue previously reported.)

I'm trying to use a keyboard shortcut to move a note from one voice to another using the instructions in the Handbook. Clicking the destination voice on the Note Input Toolbar works as expected, but the keyboard combination cmd+option+[1-4] generates a tuplet (expected behavior of cmd+[1-4]) rather than swapping the voice.

I updated Preferences > Shortcuts to update these shortcuts to cmd+option+[m|,|.|/|], and got similar results: cmd+option+m added a rehearsal mark, and cmd+option+, opened Preferences.

I've confirmed using the Keyboard Viewer app that the hardware and OS are recognizing the Option key.

Steps to reproduce:
1. Confirm not in Note Entry mode
2. Select a notehead
3. Type cmd+option+[1-4], and note that a tuplet is created instead of the note being moved

Score example attached. First measure is the starting point; second measure is what I want to end up with. The focus is on the "AND" of beat 2 in the right hand: making the lower eighth-note B-natural into a sixteenth in voice 2.

Thanks for taking a look.

Musescore 2.1.0 (871c8ce)
MacOS Sierra 10.12.6