The Ge or Gradient Ellipse element is a partly transparent ellipse which looks like it has been lit from the top.  (We think it looks a bit like the moon rising over the horizon.)

Its Property Page lets you set the following properties:

w - Width in pixels

h - Height in pixels

By setting w = h, you create a circle that looks like a rising moon.

By setting _rotation on the Advanced Properties panel, you can change the direction of the apparent lighting.

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