I have a four-part score where, in one flow, a voice is tacet. Another voice does not enter until bar 10. I set visibility to hide empty staves but the spacing is off. Adjusting note spacing did not fix it. I assumed that Dorico would first set note and bar spacing and only then hide any staves that had empty bars, but it looks like tries first to hide as many staves as possible.
I’m sure I can manually move bars around from previous or next system, but is there anything about this that I am missing?
Are you sure there aren’t any System Breaks? Are the Signposts set to Show?
As far as I know, Dorico spaces the music ‘normally’, and then just hides any empty staves.
(TBH, for 10 bars, I’d just show the additional blank staff anyway. It’s useful to see who’s “involved” in the flow at the start; and you’re not really saving any paper.)
Also it’s important to know that manual note spacing changes will not affect the casting-off at all, unless you then remove the system breaks Dorico automatically adds.
There are no system breaks.
Necessarily there will always be a system break, when all three staves are been reinstated after a two stave region.
It will be hard to say more without seeing the actual project file.
I see you have a manual Note Spacing change at the first bar. Either delete it and let your Layout Note Spacing settings do its work - or reduce the value of the manual override further, until your nine bars will be spread over two systems.