Hey, I found that the 3D Viewer is showing the board outline wrong. Instead of cutting the board in the center of the board outline track, it cuts it at the inside edge of a virtual 0.3mm wide outline, so it removes 0.15mm too much on each edge. The 2D viewer is fine. Of course this is only noticeable on small board outline features. The actual width of the board outline track doesn't change the 3D viewer, I've tested that.