Thank you Antoine.
I did not know all this as I began my modelling carrier with AFS2.
So unexperienced as I am, I just dropped the bgl (from the FSX addon Scenery folder) to MCX,
then clicked "Export Scenery" in AFS2 tsc format to a new folder and bingo, the object was ready with correct positioning information and night texture.
Maybe I had luck with the models. It also automatically loaded all needed textures from the texture folder.