Double clicking notes makes them dissapear.
I hesitate to report this because it isn't really straight-forward, but using R2443 on windows XP, try this:
1. Create a new score and enter some notes.
2. Click on one of the notes.
3. Double-click on another note.
Expected : Focus would move to note double-clicked and enter edit mode.
Result: Often, but not always. A part of the first not will vanish. Repeated double-clickings cause more to vanish, first note head, then stem, then flag.
Comments
I have noticed similar oddities with system brackets, frames, and text. See http://www.musescore.org/en/node/3786
In reply to I have noticed similar by David Bolton
When I click on a note and press [s], to enter a slur, it automatically goes into Edit mode. This is different from previous versions, and I have to hit [Esc] before I do anything else. Usually the slurs are about right and don't need any editing.
In reply to Slurs by MDMilford
This is the same as previous versions.
If you are in note entry mode then press S to start a slur and S a second time to end the slur.
If you are not in note entry mode then adding a slur switches to slur edit mode as you mention. This allows you to extend the slur over multiple notes.