recommendations on engraving old-school horn & trumpet parts that have no key signatures
I'm trying to keep the look & feel of the original IMSLP score, where the horn & trumpet parts shift frequently between instruments in different keys, and the score doesn't use a key signature for them and instead provides accidentals as necessary.
My present approach is-
First: For all affected instruments, at the beginning of the score use the Palette/Text/Block-S option, select the applied Block-S and from the Inspector un-select "Generate Key Signatures".
Second: Manually enter or make invisible accidentals as necessary.
This is a bit cumbersome, and if anyone has a better approach I would appreciate it.
Thanks, 
Comments
I don't use the Staff type change (Block-S) I keep the instruments like all of the others. Don't suppress the key signature because it forces you to enter unnecessary accidentals and make them invisible. Use the atonal key signature on these instruments. It's found in the advanced workspace and is the one with a light gray X on it. The X won't show up in the score. When you apply it press the ctrl key while you click or drag it. Press ctrl then click or drag then release the mouse then release ctrl. You will need to do this at every key change but won't need to do it at instrument changes if you change from Horn if F to Horn in C for example.
Since version 3.3 you can right click a measure after the instrument change and edit the short instrument name so the instrument's label will change properly at the next system.
In you picture, it looks like the Trumpet's label changes at the start of the system but the "in F" is later in the system. You will need to do the instrument change on the first measure and make it invisible, then use staff text to show "in F"
There are other ways to do all of this, but in my experience this is the easiest and cleanest method in the current version.
In reply to I don't use the Staff type… by mike320
Thanks, this is exactly what I was looking for.