silent material of fbx impotring

I have a trouble in bge, after pressing P key some objects becomes invisible.
I think a problem is in material of fbx impotring.
And i don’t know, may be this is a bug.
Please see my scene.

There are multiple problems in this scene :frowning:

  1. Overlapping faces (Objects have faces at same place makes flashy grid (Known Z fighting))
  2. Transparency is setted to materials, may couse hidden faces too, and that planes do not need alpha indeed.
  3. Many textures was mapped to ‘Ambient’ Not to ‘Diffuse Colour’ (Why?)
  4. Doubles in mesh. Some cubes contains doubles (Two ore more vertices are same place) Swhitch to editmode, select all and press ‘remove doubles’)
  5. Normals. Some objects has flipped normals (Get familiar with normals, Google ‘Face normals’).
  6. Some UV maps plots different texture than material. (Why?)

Thank you for anwer!
Useful info!
But i found my problem - it is edge split modifier.