Maybe I did this wrong. In TrueSpace I made a cylinder: x=12, y=12, z=0.01. Then imported it into Vue and greatly enlarged it. Still was darker at the horizon. (I did not tilt as I didn't understand the point of doing so since it still would be a flat disk blocking the light.) Then I played with reflection and transparency to ge this result; not perfect but I also like the slight area of lightness in the water at the horizon. But if I wanted plain clear horizon line without that area of brightness...I couldn't do it.