But no matter the combo of dynamics I use in the percussion map,
I cannot seem to get the playback of the percussion slot to reflect any dynamics used in the score.
Are the dynamics available as playing techniques not able to be used as condition triggers for the percussion maps?
No, I’m afraid those don’t map on to Dorico’s dynamics. We included them because they’re part of the Cubase expression map format, but it turns out that they don’t map well onto Dorico’s idea of a continuous dynamic profile.
Since some libraries do have different samples based on dynamic levels, I would wonder about a future update where the condition fields in the expression maps could offer dynamics as an option (rather than being thought of as playing techniques, they are just condition variables attached to a broader playing technique). So you could do stuff with different base switches such as:
if < = p then cue this sample;
if > = mf then cue that sample;