I have some basic partial pedaling working. I can get the release time to change according to the CC64 value, and it continuously changes using ampeg_dynamic=1 as you suggested. That's cool!
Now, I need to set three ranges, for example when CC64 is: range 0-32, normal 0.8 second release. Range 33-64, variable depending on number. Range 65-127, full sustain (or we can just set to a full 10 or 12 seconds).
Can this be done with custom curves? "locc64=33 hicc64=64" doesn't seem to filter out below 33 and above 64.