I am testing the new raytracing capabilities on a project. A few objects are composited over some footage. They look great, but they take really a long time to render, so I prefer to pre-render 3d elements with an alpha channel and then make a composite. Everything works fine, except a layer I put there set to cast shadows only.
When I turn off every 2d layer in the background, the layer set to only cast shadows becomes visible. It doesn't happen when I switch over to Classic 3d.