Position and water level always make a difference. The water is above the camera currently, and not the renderer does not render under water. By panning the camera up a tad I was able to see the water. But something is up with the preview as it usually pretty much won't update. Might wanna simplify down some.
Position matters because water is a plane object. Depending on where the plane is located on the planet and the radius etc the height becomes rapidly different. Using water really has the best results near the center from what I've done. Also since it wont render below water, it becomes invisible above the camera.
