It happens always! But only today i noticed that this is exactly because i used mirror modifier. Why it works ok in Shift +Z, but doesnt work at all in the game?
How to fix this horror? Multitexture doesnt help, Recalculate normals doesnt help, Remove doubles doesnt help...
One screen - render Shift Z
The other - render BGE Game engine
the third - render Flip direction applied BGE (wrong view from the front of the building disappeared, but still other sides have it