Hang on: is there a midi thru box involved now?
As i mentioned in my first post, the Play doesn’t feature proper MIDI Thru, hence why i suggested a MIDI Thru Box.
Your setup should look something like this:
Regarding implementation. This was requested 2 years ago, but back then declined by Poylend:
If you feel like you want to try it again, we can either open this request up again and see if this rqeuest garners enough votes/traction to make them reconsider it or you could start a new request specific for Poly Aftertouch passthrough.