My floor plan looks empty / my windows don’t show as cut — why?

Before assuming the model is broken, check View Range (Properties → View Range → Edit…) and the crop region. A plan is a horizontal cut: the Cut Plane usually sits about 1.20 m above the level, so anything above it (say a window with a 2.00 m sill) won’t be cut and shows differently or not at all — either lower the window or raise the Cut Plane. To see geometry below the level, set View Depth to Unlimited or down to Level 0. Full steps: View range cut plane →