I know it's hard to tell from the photo, but the 3D view shows all the exterior trim to be curved, not straight i.e. it's wrapping around the curved wall. In plan view, if everything was straight, the right and left side would show up straight, but they follow the curve of the wall as if a line had been drawn from the center of the circle wall to a point perpendicular to the wall. The inner contents of the window do stay straight. Here again, in reality, that's the way most windows work - a series of straight windows around a curved wall.
BTW, I asked for help on an issue, not criticism. If you're NOT going to give me help on this topic, please be courteous and stop responding to my posts.