I don’t know. There’s a lot going on here. In my opinion, it’s an exploit.
If you go and put a signature track in a folder. and then close the folder, there is no data part on the folder to allow us to move the signatures.
However! Once we sneak a MIDI track in the folder, having created a part for it, this will make the folder show a data part. If we move that part, all hell breaks loose. Because the signature events ALSO move with the part (in my opinion they shouldn’t), and what’s more, the MIDI part is dropped after it has been dragged a number of beats later. But this number of beats might lead the part to not fall on a bar’s one, ok, this doesn’t matter much, but it does matter to the signature events, that are forced to move around in order to be in proper places.
Well, if someone made sense of what I just wrote, my congratulations.
I believe signature events and MIDI parts were not meant to move together. In this case, we can move them, but I feel we shouldn’t be able to move them.
It’s a fairly easy issue to study though. Just put a signature track in a folder, start creating signatures, one per measure. 4/4 one bar, 3/4 one bar, 2/4 one bar, 1/4 one bar, 7/8, 6/8, 5/8, 4/8, 3/8 all one bar each. Move them around, everything’s fine right? Then create a MIDI track, draw in a MIDI part, stash it in the folder too. Once you drag the “compiled part” of the folder to a specific place that would NOT be the one of any bar, the part goes there, the signatures freak out trying to make sense of where they’re allowed to be, and finally the part ends up in the “wrong” place (compared to where it was supposed to go just before letting off the mouse button for the drop).
Just don’t allow dragging time signatures along with MIDI, or if it is supposed to be allowed as an operation, it should function as Insert Time instead?