Dragging the ends of trills causes measures to move around erratically
1) Select one of the last two trills in the linked score
2) Click and drag the end of the trill left and right
The measures in the score rearrange themselves erratically, making it impossible to position the end of the trill where you want it. A work around is to copy the measure into a different score, adjust it there, and copy it back.
I just noticed that this seems to only happen because I have a hidden staff at the top of my score.
(I added a new staff to the score, right clicked on it, clicked "Staff/Part Properties...", and changed "Hide When Empty" to "Always")
I was able to reproduce it on a different score by adding a hidden staff, then adding notes until the measures could rearrange themselves.