MusicXML - bad export of trill lines
Ubuntu 14.04, GIT commit: a98b748
I see similar results on 2.0.2, 2.0.3, and the master. Trills are either not exported at all, or are exported as "stop" elements with no "start", or they have a "number" of 0 which is invalid. Try the following:
1) load attached file
2) export to MusicXML
3) import resulting file
Result: trills are lost. Examination of the MusicXML file shows "stop" elements with no "start", and errors are printed to the console about this both on export and import.
I am not sure what conditions lead to a "number" of "0", but you can see this happening in https://musescore.org/en/node/102111. I thought it might have something to do with the grace notes, but my test case doesn't reproduce this, so I'm not sure what the variable is. Maybe the existence of notes on another staff.