I had wonderful help with the Grabbing (finding the bugs) - now wonderful functioning.
BUT struggle the whole weekend: How can I use the index finger (Oculust Quest Controller) to push a button. How to cast with the index finger a ray that a) activates buttons in distance (with trigger button) b) Grab and Moves distant objects with trigger button. I tried with VRTK but the documentation and current state dont match that made it too difficult