Q-Plane setup - basic setup problem

I am in the process of setting up a quad tailsitter FW-VTOL.
Being familiar with both Arducopter and Arduplane and I thought I was almost there with the basic Qplane setup ( it seemd to work on the bench - not flown yet).

Then suddenly the Qplane flight modes (like QLOITER) dissaperas and are no longer available in the Mission Planner Config menu. The other config Q-fields are there but contains no text as if they are obsolete.
In Mission Planner (in the connect-field upper right) the vehicle is no longer “Fixed Wing” but VTOL-QUADCOPTER. On the map, the vehicle shows as a quad, not a plane.

I’ve tried to load new fixed wing firmware several times following this procedure:

  1. After loading new firmware, setting Q_enable = 1
  2. Refresh (All Q-parameters are now available…)
  3. Write all parameters

If I the disconnect and connect again, the Q-setup is now longer valid, the “Fixed Wing” has become a VTOL-QUADCOPTER with the Q-parameters unavailable.

Please help, driving me nuts…