The surfaces are triangulated so you see the contours of the many triangles that make up the various surfaces.
You could convert the object to a Morph, clean it up, modify the color of any edge, the save it back as an object or Window so you can place it as such.
While editing the Morph you can also try to select edges that divide two co-planar faces and delete them, thus reducing the number of triangles and edges.
It is also possible to select edges and set them to Hidden, so they will not be visible.
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