Not sure if I'm helping. Your photo shows a door with the rounded corners and appears to show a square corner trim panel laying on it. With the rounded door the trim panel should match the rounded corner of the door. I see the screw holes in the door frame, in your photo. Those screws would be only slightly inside the edge of the finished trim panel and the trim panel should lay just at the edge of the inside surface of the door and match the contour. With trim installed on the door, you would see almost none of the inside painted surface of the door. With the door closed, you would be able to very slightly see the hinge pillar at the front of the door, because the door opening is square and the door is rounded, which creates a small "triangle", but it's not large enough to really matter and is the way it was made originally. A square trim panel would fill the gap but would hang over the rounded edge of the door. Tried to get you a photo but couldn't get it to download from my camera. Hopefully the explanation helps.