"Prepare Mission" for Gazelle? Does it Work?

The manual only indicates support for A-10C and Ka-50.

I would like to have the mission start with the Vivienne active. So, after getting ready everything else in the mission editor, I:

(1) click on "Prepare Mission"

(2) start up all the avionics

(3) quit

(4) back in mission editor, I hit "Save"

But when I actually run the mission, everything is back to square 1. Am I missing anything?

To me the prepare mission is used to program the ABRIS for the KA50, and I don't know what for A10 (don't fly fixed wing). Adding different loadable flight plans and graphic annotations on the map, which requires the use of the ABRIS interface. It doesn't allow you to choose wheter it is on or off at start up. In the case of the gazelle, since the NADIR can manage only one flight plan that you define in the ME (or add manually in the sim), I don't see the point for prepare mission.