Found another small issue:
When I create a player with more than one instrument (e.g. drums), in the setup view (“Einrichtung”) and also in the page view (Seitenansicht) I see only the first instrument. I have to switch to “Fortlaufende Ansicht” (sorry, German version) and enter notes to the other instruments in order to see those in the mentioned views. This is a bit confusing.
It’s intended that it should work this way: in galley view, you can see all of the instruments belonging to a player, but in page view you see only the current instrument, with automatic instrument changes created at the appropriate points.
I created a player with multiple instruments for Horn 2 and 3 - and Trumpet 1 and 2
Strange enough, the empty staves for both trumpets are shown, the empty staves for horn not.
I don’t understand. The settings are the same for both instruments.
Are you sure there’s no manual setting on “visibility” set on a break? Make sure Reset is set for all instruments before the point you’re looking at.
We can keep guessing but it’ll be quicker if you upload the project.
You’ll probably need to send a minimal example file then…
I think what’s going on is this:
Each of your players holds multiple instruments.
Your Layout Options allow instrument changes to take place automatically in page view.
Typically a horn player can’t play two horns simultaneously, nor can a trumpet player play two trumpets simultaneously, but that’s what you’ve told these players to do, from bars 15-18.
At bar 19, you’ve given Horn 3 some notes, so Dorico knows that it can hide Hn2’s stave (because instrument changes are turned on the assumption is that 99% of the time, each player only plays one instrument).
Until you give either Trumpet 1 or Trumpet 2 (which are held by the same player) some notes in bar 19 onwards, Dorico doesn’t know which stave to continue showing, so it shows both. As soon as you add a note on either of the Trumpet staves, Dorico will hide the other trumpet stave.
If you don’t want Dorico to do this, turn off Instrument Changes at Layout Options > Players > Instrument Changes.
Ok. Yes, yes, yes - that’s a good way to think about it…thanx for sharing Leo.
It’s just a very special case. The conductor wants a reduction of a larger ensemble but he wants the 2 horns (2 & 3)to see both voices and the 2 trumpet players to see both voices.
I tried the same set-up with divisi for trumpet and horns which would work better for me BUT he wants the 1st trumpet in F and the 2nd trumpet in Bb and I couldn’t find out how to divide the divisi into 2 different instruments (I guess it’s not possible and not the purpose of divisi anyway).
Like I said: a very special layout which the conductor asks…
Why not stick with one player per instrument, then assign multiple horn players to a single part layout and multiple trumpet players to another single part layout?
Yes, I thought about that, too…
Hmmm…maybe I should do it like this, yes. Then all staves would be visible the whole time - that’s what I want anyway, cause in this special case I didn’t want to work in galley view. But maybe I should just switch to galley view, then it doesn’t matter - but I’m copying a conductor score and for reasons of clarity, page view feels better… Lots of possibilities 
