Simply look at the screenshots I posted above. In the first shot, the shadow is visible, the 2nd its not. The camera xyz has not changed, just the camera pan, in this case a slightly raised view. So if this was a camera inside the cast zone, why would it work in the first and not the 2nd?

Note: this problem is the same, regardless of where the camera is in the level. So while I accept their are some issues with camera's inside the shadow clipping plane, I don't understand how without moving the cameras location the shadow is effected...

To clarify: If shadows are going to pop on and off with little or no warning, or reason, then they are pretty useless to me.