Enabling passing polyphonic aftertouch in the VST wrapper causes notes to cut off prematurely with Fxpansion's BFD2.
BFD2 can be set to use polyphonic aftertouch to detect individual cymbal "chokes", i.e. manually grabbing the cymbal to dampen out the ringing. However, enabling the polyphonic aftertouch causes BFD2 to cut the decay of all of the drum hits, almost like a choke, but more like the result of a short sustain and/or release setting.