After investigation using my model viewer I found that basically both of your objects are "open".
Let me explain:
You load the object without moving it, but you move the camera below the model and point the camera to it.
If you move the camera above the model you can see that...well you can't see much as there are no faces...
But wait if I turn on wireframes I can see some edges which belong to faces on the top side of the left star.
After moving into the model and looking up you can see the faces facing in the wrong direction.
Also your UV's and normals seem to suffer from it.
Hope that all wasn't intentional, but let me know if you still have lighting problems after revisiting your model