Model turns black in another viewangle

http://alexaz.net/img/black.png

In this picture you can see that on the right the model becomes black in different viewangle. Why? How do i fix this? (Right picture quality is lower, because enlarged with paint.)

its beacuse its racists

I believe it has something to do with the origin of the model. IE if it’s in the very middle of the grid in the modeling program.

yes, its in 0,0,0 in 3ds max and the cabin canopy is sphere in middle of other object

EDIT:

So yeah, i moved it a lil bit away from the grid center and i still think its the sphere in middle of the other object:

http://www.alexaz.net/img/left.PNG

So ok, how do i cut the sphere so it fits perfectly?

What did you use to compile? Kathar had a similar problem way back
http://www.facepunch.com/showthread.php?t=545204
and he fixed it by using GUIstudioMDL instead of StudioCompiler