Dorico Drumset not working

I am writing a piece with a drum set. I also own BBC symphonic orchestra by spitfire audio. Every time I load the playback template the drum set is “filled” (only the snares) with the appropriate sound. However, I want to use the GM drumset sound and not the BBC symphonic orchestra sound. I then load the drum set sound in a separate Halion sonic player and load it into the drumset instrument. However, when I do that, the drumset only plays one sound (the whistle sound). Is it because it is still using the BBC symphonic playback template? Is it possible to change the playback template of one instrument?

Welcome to the forum, Quin.

What Expression Map (click cogwheel icon) do you have assigned to the MIDI channel matching the HALion drum sound(s)?