MAVLink and Custom flight mode

Hi there !

I’m using Copter version 3.6.7, and trying to run the SITL simulation with WSL.
the SITL is running great, and I can simulate my plans and everything work flawlessly.

I have been trying to setup a new custom flight mode,
after following (precisely, as I can) the Documentation about the new flight modes (3.6 and above) :

I have tried once again to boot the SITL, wit the WSL, but I couldn’t find the new mode to change to.
I tried the specific enum number to change to, and the enum “name”, I also tried to add a new line for entry value at the ardupilotmega.xml (step 7), and still it doesn’t appear.

I would be happy to understand where have I gone wrong and/or missed somthing.

Thank you !!