Many kits have many more cymbals than others, but the additional cymbals are handled with MIDI notes that are not used with the main 'standard' 3 cymbals (2 crashes and a ride). But for most of the EZX's, the mappings are relatively consistent with respect to kick, bass, toms, hats, and cymbals.

While there are some subtle differences in MIDI notes across the EZX expansion packs, for the most part, these pertain mainly to the packs that are what I would call 'non-typical' drum kits - such as the Latin Percussion kit, the Twisted Kit, etc. I own every EZX expansion and yes I am aware of how MIDI notes can differ across the different expansion packs, and I also have been looking at their MIDI layout pdf's quite extensively as I figure this out. So at least you can get the mapping from the DKD designer done, but you'd still need to mapping on the EZDrummer expansion kits as well. If you pursue this, there's already a Scriptor called Drum Kit Desinger Remapper that goes from DKD to GM. I was taking a look at that thru a Scriptor object but realized that you'd need a separate Scriptor for each EZDrummer kit and for the Superior Drummer 2 as well. The maps are in a PDF file for each EZDrummer expansion kit, but only if you purchase those kits. So you'd have to know where the EZDrummer MIDI is coming from and create a map for the EZDrummer expansion to DKD. I doubt anyone would write a map like this from EZDrummer to DKD because the MIDI supplied with the expansion kits can be different across those EZDrummer expansion kits. That's because those notes trigger different samples of the same drum kit pieces but don't follow any GM standard because there is no standard for those additional drum pieces that DKD and EZDrummer use. but other than that, the notes are all different.

Ezdrummer midi mapping