None of the gongs have the correct sound, I hear a soft tom tom kind of sound when they play back or by clicking on their notes. I reasigned them again and did a mixer reset, but no gong sound.
Looks like the staff that appears when choosing a gong sound, it in fact a GM percussion kit. When entering notes playing on my midi keyboard, I can hear all the percussion instruments as in a GM kit. Any suggestions how to bring this back to the Gong instrument alone?
I found that if you delete an instrument ensemble not used or added by mistake then add back Gongs or Marktree that it gets weird.
My Marktree plays a low pedal tone in like a contra contra Bassoon! Ha
I am trying to figure out how to edit the actual midi note so I can reassign it to correct pitch. 
Percussion sounds for NP in Dorico are still something of a work-in-progress. Due to being a relatively new feature, and not many other percussion templates to go by for reference (yet) there will probably be errors in the mapping that need to be ironed out.
If you open the Percussion Map, you should be able to see the list of sounds, and also if they’re wrongly mapped, or not mapped at all. All our sounds are included, but many are just mapped to “Conga (low)” in lack of a better option (or an option I couldn’t find while producing the map). It would probably be easier to make a correction yourself, directly in the percussion map, than to circumvent it from the score. Editing the percussion is really no more hard than assigning manual percussion sounds in Sibelius. The map changes should be saved with your score, unless I’m mistaken. You may need to unlock it, clicking the lock icon, to allow editing.
I am trying to get the ride cymbal (high) to sound, but even though I assign it to the correct sound in the Percussion Maps, it defaults to piano. This is also showing in the mixer as shown in the screenshot.
Screen Shot 2018-06-02 at 08.46.05.png
Hmm, I’m not sure why that is, to be honest. The program assignment is managed by the Playback Template. Maybe it doesn’t resolve to the correct instrument if the map is missing an entry, or something. Steinberg are much more qualified to answer this than myself. This system is completely new to all of us, so there may still be kinks or loopholes like that which haven’t been quite resolved yet.
I’m having the same exact issue as Andre with the ride cymbal producing a piano sound even though I’ve re-mapped it correctly. I just went into the instrument under the play tab and changed the channel to the drum set channel and the ride then started playing correctly. However, I still can’t explain why there are several piano tracks that note performer created. Anyone know how to get rid of them?
I realized from using the new Finale implementation of NotePerformer that if NP does not recognize the instrument name (in the column it uses to look for the name) the sound will default to Piano. SO I am guessing that if the Dorico compatible version of NP does not find an instrument name it recognizes (wherever it searches for it) you will find a Piano sound implemented instead.
Presumably this will all get better as Dorico and NP become better acquainted with each other. NP Dorico is still a beta, after all.
Not that it has any practical consequence, 
but I believe the “piano” fallback solution is purely coincidental. I’m guessing that Dorico and Finale both chooses to play the note with a piano patch if a percussion sound doesn’t exist in the map.
NotePerformer’s “fallback” instrument, or the sound you get when a patch isn’t assigned (Bank/Program 0:0) is a trumpet sound.