Need to invert a tilt sensor

I have tried to control my Hörmann garage doors with a Shelly device and a tilt sensor.
Set up as follows
Shelly 1 to open and close the door.
Vision Z-wave tilt sensor, off when door is closed otherwise on.
To be able to use the Cynical behaviour plugin, model Garage opener I need to invert the output from the tilt sensor.

I tried howartp’s Variable device plugin and a variable to reverse the output but the Cynical behaviour plugin doesn’t accept the Variable Device as a sensor.

Anybody that have an idea how to solve the problem?