Sometimes only the FS default groundtexture visible

[Bluebook]

Good evening, i purchased the KDFW Scenery for FS9 today. This is not the first one of your great sceneries i bought, and they all are running very well. This time i have a litte probleme with the Ground textures. Sometimes i only see the fs default ground textures, but all other objects of the scenery are visible (Terminal, vehicles, etc.) 
I do not use any mesh, and check it out for double afcad file. I also change the layer in the settings (act. number 2, first is aes), and reinstall it.
Thanks in advance...........Dirk

[virtuali]

Check you mesh complexity and resolution setting, and be sure they are as indicate in the KDFW manual, in the design notes section.