Drum set playing different kit, then Dorico 4 crashing

When I input notes I get the full orchestral kit instead of full drum set. Then when I try added open sign to high-hat the entire application quits. Tried restarting my computer a few times.
Tempted to use the Time Machine to return to previous OS and Dorico 3.5

Welcome to the forum, @John_Benware. Sorry to hear you’re having problems! It sounds like you are encountering a known bug that causes Dorico to quit if you try to add a playing technique to a percussion kit with more than one note selected. If you make sure that you have only a single note selected before you add your open marking, it should be OK.

I’m very sorry for the inconvenience caused by this crash. I hope that now you know the cause you will be able to work around it for the time being. An initial maintenance update with this fix and a bunch of others will be coming at the start of February.

:+1: Thank you for reading and responding to all these posts.