(I had some return tracks on the picture⦠- the tab was just closedā¦)
But I could make it work now
H O O R A Y ! 
When I was setting up everything like you said I was like āwell, thatās almost where i started, before asking the forumā¦ā, but instead of (de)activating the reverb-effect via my midi-controller I tried it with the āsend-buttonā on my monome⦠so just one button did the trick
silly me.
I now see that on the one hand I was thinking too complicated and on the other just dumb⦠Maybe a result of way too less sleep (to protect myself against embarrassment, lol)
Thank You Very Much Dear @elquinto & @jasonw22 For The Hints & Helping Me out! 