I had a D4 long time ago but exchanged it for the following model DM5, that still I own.
I had sampled some sounds from D4 (a borrowed one, later) that weren't anymore on DM5, but didn't have the patience to do them multi velocity samples.
But actually I did it with a few DM5 Snare sounds for use them in Battery.
The way you did the plugin is ok for me (the different note for different groups of sound seems better to me): I can just use those sounds I need,
and loading all the instances inside a VEPRO instance make it easily playable with one midi channel only and less audio channels inside Cubase.
The different note for different groups of sound seems better to me.
A Kontakt version however would be fine.
I'm using the Forgotten Keys drum machines infact.
Uh, I can confirm that D4 (as DM5) has a pitch tuning for every sound...
and the note playing muting for sounds assigned to the same group (like closed hihat and open hihat, or same cymbal hits), but I doubt you can implement the latter in your plugin...
but in Kontakt is doable.
all the best

