Percussion Map Issue

I imported a percussion kit from a file where playback is working fine. The playback template is set up for all of these instruments, but it did not load them as is often the case. However, in this case I manually loaded up the VSTs, Expression Maps, and Percussion Maps but it is still not playing back correctly. It plays the first listed instrument in the percussion map no matter which instrument I enter notes for.
Percussion Map Issue.dorico.zip (3.4 MB)

I don’t have your VST but I opened the project and all the instruments are routed to the same channel:

What do you see? Can you screenshot a couple of instruments setup?

What I see is identical. Everything looks like it should be working (or else I would have just fixed it myself). But Dorico sends C2 no matter which instrument is played, rather than following the percussion map.

I will try to investigate more for you when I get a chance.