
Even though this is a known bug, due to the recent resurgence of flat-shaded 3D i figured i might draw some attention to it again.
When importing a mesh that has flat-shaded polygons, its normals are ( often ) generated incorrectly. For instance, here's what happens when you create a Box in MilkShape ..

.. and then export it as .3ds file & import it into ZGameEditor.

As you can see some of the normals are incorrect. And just for the record, when you import the .3ds file back into MilkShape the normals are just fine.
K