@Inveracity you can make velocity layers with the audio loop player looks like gain modulation (velocity). but if you put for example 4 layers, it would be necessary to make 4 velocity envelopes which would be extremely long to do each time. So stay on the sampler and you can also add gain or filter velocity envelopes.

@d-healey thanks for that they also have reaper templates so should be able to use all of those, thanks.

@Dan-Korneff Are you referring to the regular GM hats open/close/foot or the variable hats?
My plugins utilize both for compatibility.

The design I came up with for the variable hats is unique to my plugins, and they work with e-drums. The basic principle is that there are 2 notes: one for the hat tip and the other for the edge. You use CC4 to control the openness.

The way I accomplished that is by having parallel samplers: 6 for the tip and 6 for the edge. Each goes like: tightly closed/ closed/ 25% open/ 50% open/ 75% open/ 100% open. So, by operating CC4, you move between those samplers and mute notes in others that are not within a specified range.

This system is not 100% compatible with e-drums out of the box. They still need to set all of their tip to one note and all of their edge to another. I made the system that is the most practical, in my opinion, and can work with either e-drums or keyboard controllers, as well as being able to edit things easily with a mouse.

I'll gladly share the scripts with you if this is the system you want to implement.