[Question} Mdx files disappeared

[magnivore]

Hi all guys.
I'm a long time not working on modeling
But a week ago, I decided to return to this beautiful and interesting case. I started a new (small) project, the city Strahnbard.
Immediately after the start faced a serious challenge.
All mdx files are displayed in noggit fine, but in the game, they disappeared. (screens bellow)

Noggit



WoW



And Light's problem



Questions can be noobish, but very much forgotten. ) I hope for your help, colleagues.