hiding rest does not work

Dear advanced users and developers.

In the attachment, I cannot remove the rests in the first bar.
test.dorico.zip (815 KB)
I would like to have the first bar as an informative notation similar to legend.
Could anyone explain the reason why I cannot remove the rests in the first bar, and how I can do it?
“CTRL + R” and the option in the properties panel do not affect.

I find that I can remove them all apart from the Timpani and Wood Block ones.

You need another solution for the Timpani (such as using real notes scaled down) - Dorico will not let you hide the rest that a grace note is attached to, because it can only hide a voice that is actually empty.
For Percussion you’ll need to think of another way. Remove Rests/Starts Voice/Ends Voice do not work on percussion kits.

Thank you very much for your help!
The attachment was a reduced file. It is amazing it suddenly works.

Could you try the following attachment?
test2.dorico.zip (816 KB)
Do the extra pages before the music frame affect?

I am very confused.
Sorry and thanks again.

It’s nothing to do with the extra pages.
In your original “Test” file, the first bar rests are all explicit (you’ll see them as black rather than grey if you go View > Signposts > Implicit Rests).
In your “Test 2” file, none of the rests are explicit; they’re all grey.

In your original “Test file”, if I “Remove Rests” on the first bar, Dorico automatically recognises that the second bar’s rests must be made explicity (which you can do manually by selecting and hitting O to turn on Force Duration).
For some reason that isn’t happening in your “Test 2” file.

All you need to understand is this:
In order for Dorico to be able to remove rests, something explicit (whether a note or a rest) must exist somewhere on that stave, in that flow. It could be a single note at bar 763, or it could be a single bar rest at bar 1289 that has been made explicit by you selecting it and typing O.

Thank you very much for your kind explanation!
I’ve understood it now!