OK i have it working.
The problem i fixed on the pfm3 was only in USB that filter out the polyAT data.
It should work with the version 0.100z you have through DIN5.
Puredata is nice but the version installed by default on Ubuntu 20.4 has a bug in the polytouchout object
It was sending channel Aftertouch instead of the polyphonic AT
It was fixed here :
https://github.com/pure-data/pure-data/commit/647c0291064416c415ed8dc6a01ae02ac94fdd0dSo i had to compile the latest version.
I modifed a little the patch you sent me to make an easy test.
In the matrix you can use:
PolyA / 10.0 / O*Fq
an we can clearly hear the polyAT effects the frequency of only one note.
Thanks