Muse Percussion doesn't play notes with tremolos
Muse Percussion seems to ignore notes with tremolos.
This is how I would normally do cymbal rolls in MuseScore, but using Muse Percussion, the cymbal only plays the eighth note in the second measure.
It works fine with the default MuseScore General soundfont, but not with Muse Percussion.
EDIT: Apparently, it works when using a cymbal in a drumkit, but not the "Cymbal" instrument. Weird.
Comments
It depends on which type of cymbal you have selected for that line in the Mixer. The tremolo should work for "Suspended Cymbal" (although you might want to reduce the number of tremolo strokes to 3?), but not for "Piatti" (i.e. cymbals held in the hands and crashed together).