How to make a CGL file ? I did not understand the manipulation to do!

Hello ! I’m having a hard time understanding how to make a CGL file ! If I see
the SDK screenshots
https://docs.flightsimulator.com/html/Samples_And_Tutorials/Samples/Sceneries/SimpleAerial.htm
it’s easy, but when I go to Devmode (Current Version: 1.32.7.0.), the
Devmode/New Project does not point to SimpleAerial.xml ! I have the clear
impression that the Devmode is buggy, since it does not see SimpleAerial.xml !
I have already deleted the MSFS_SDK_Core_Installer_0.21.1.0.msi, updated
windows 10, rebooted windows 10, reinstalled
MSFS_SDK_Core_Installer_0.21.1.0.msi - and I still have the same problem ! And
if I go through Devmode/new project, and I develop up to Scenery BGL and
Inspector + add asset group, I find myself unable to put a CGL asset group!
And I still haven’t figured out how to do it ! Regards, Marc

Not too sure why you can’t open the sample cgl project, but one thing which
might help – the CGL asset is added to the top level of your project, rather
than any Scenery asset. So if you already have a project with any sort of
scenery asset, make sure you click on the top level in the Project Editor, in
the inspector Add Asset Group. You can then add a CGL asset. Of course you can
start with a new project, then add the asset.