Mission Maker Dronie does not work

Ground Control Software Tower
1

Has anybody tested this ?
Pushing the dronie button does nothing.
Follow Me works excellent.

ArduCopter 3.6.8
Mission Maker 4.0.0

2

Made tests with
Tower 4.0.0 and ArduCopter 3.6.8
Tower 4.0.0 and ArduCopter 3.6.7
Mission Maker 4.0.0 and ArduCopter 3.6.8
Mission Maker 4.0.0 and ArduCopter 3.6.7
No change…

There are videos on youtube
showing dronie working.
So I wonder if anybody can share an experience.