Bug when adding new "fake" barlines
This seems to be a pretty drastic bug:
I have some tuplets in a score (quadruplets, in fact) which need to cross a barline (this seems to be the best way to notate what I want here - and certainly the easiest to read). The piece is in 4/4 at this point, and since Musescore doesn't allow tuplets to cross a "real" barline (not so great), I used the workaround described here: https://musescore.org/node/15448.
I created an invisible 8/4 bar, and split it in half with a "fake" barline by clicking on the 5th beat (rest or note, as applicable) in the top stave of each system. I then double-clicked on the normal barline in the barlines palette and dragged the barline downwards to cover each system. Fortunately, dragging this barline downwards also splits the quadruplets at the correct point - great!
After completing the above process, all the "fake" barlines initially show in the score and in each instrumental part which corresponds to the top stave in each system - which at first seems good. However, the same "fake" barline is missing in the rest of the parts in each system - not so good!
After saving and reopening the score, the "fake" barlines have all disappeared in both the score and parts, which of course is... really, really bad!
(Musescore 2.0.1 on Windows).
See the attached score and gif file (to see a visual walkthrough of the above process in order to help reproduce the issue...)