I am attempting to play Witcher 1 Enhanced Edition, and have an artifact which makes the game almost unplayable. There is a flickering trapezoid almost directly in the middle of the screen. I took a screenshot of what it looks like in the game:

This almost represents the exact shape of the artifact:

Is there any way of removing this artifact? This occurs in the vanilla Steam version as well as GOG version whether I am in Cinema mode or not. It does not show up when played without Vorpx.
Any advice is greatly appreciated.