I'm gonna go to bed now, the fact stands that the updated addon manager/couatl, whatever it was, fixed the reappearing of GSX with the couatl updater. That's all I was after.
Reappearing of that caused the ctrl + f12 to work in FSX again, and if I would then choose a gate, an error would pop up since GSX has been uninstalled in CP.
But I don't have any more patience to play around with this - my sceneries are working again, gsx doesn't start up with ctrl + f12, and maybe some of these days, I might install GSX again to test it with AES. I had a problem of disappearing vehicles coming to my aircraft when AES was enabled for the airport.
All I ever wanted is nice animations of vehicles and gate control of AES.