LOL the first thing to get out of the way, was pattern mode listening to Midi OMNI as default.
So I always triggered a pattern instead of a note in my first efforts.
Next obstacle were wrong note descriptions the Maschine Mackie control editor.
For example “C-1” (which doesn’t trigger correctly) has to be changed to “C1” in the controller editor.
There should definitely be easier ways to use widespread external controllers, by offering some kind of templates for this purpose from both sides: NI and Steinberg. Else every user has to find his way from scratch.
I now got the basic triggering going.