Individual percussion instrument endpoints in a percussion kit

Is it possible to set different endpoints for different instruments in a percussion kit? I could have sworn that I had figured out how to do this around November of last year when I started learning Dorico and was setting up percussion kits for a project. I am routing to an ARIA multi and have various Garritan percussion libraries on different channels. But, now, searching for what I believed I had done, and then doing a lot of searching in forums and help and on the web, I can’t find anything. I did learn how to switch channels for a particular percussion technique for the snare drum (brush stir) as the MIDI note was the same for a normal stick strike in one library and the stir in another.

On a related note. I also believed that I had found a way to create a mixer for an individual instrument in a percussion kit, which is very useful for libraries that have very different sound levels for the different percussion instruments within them.

I am transferring a two hour and fifteen minute sung-through musical from Finale to Dorico and would prefer to use the Garritan libraries for now as those are what I composed it to and also used to create my demo audio file.

As I was searching for a solution I came across a Facebook video which shows how to map instruments in a percussion kit to different sound libraries. In play mode, the guy clicked on an instrument in his percussion kit and that selected and highlighted it. So, I’m not going crazy, because when I click on an individual instrument in a percussion kit, nothing happens, which has been driving me crazy. Have I accidentally changed a setting somewhere that prevents selecting individual instruments in percussion kits? My memories from months ago of being able to do this are real. I even created a new project and set up one unpitched percussion player and a kit with just a snare drum in it. It is the default Halion Sonic Iconica Sketch snare drum.