Details: Design Explorer Information dialog appears:
"Board boundary is incomplete - calculated boundary will be used. Check that the boundary on the keep out layer is closed, with track ends touching at their centers."
Answer: P*otel 3D viewer must see a keepout boundary to house all other primitives inside it including mechanical tracks, if a mechanical track for example is used as a boundary to house all primitives inside then P*otel will see this as an incomplete boundary, even though there is a keepout boundary already defined inside it, the CAM viewer will only display and generate a 3D image for all primitive inside a keepout.