When I use the split flow function, dorico will move the dynamic of my first player about 40-50 bars later then it should be. It also adds the missing bars to the end of the last cue, so I end up having a bunch of empty staves with just dynamics. I did a short video to show you:
Wierdly, when dublicating the instrument, the second one doesnt behave like that. But I also tried deleting the trumpet, that way, the saxes dynamics will be moved. Hell, what?! !
At the beginning of Cue 2 you have bar 11, bar 12 then another bar 12. I suspect that this flow originated as MusicXML that you’ve imported in, and that if you turn on Time Signature signposts you’ll find lots of extraneous red time signatures (with bar number changes attached to them).
If that’s the case, you need to sort those out first, probably by deleting the barlines that precede each red time signature signpost, then double check that the automated bar numbers are consecutive, then try splitting the flow again.