I have 2 render layers, to which I add all objects, lights and cameras. on layer1 I set it so that it is a color render, and layer 2 I set so that it is a shadow render (using the little checkboxes) and do nothing else to the render layers. I reder the image as multilayered psd file. Now after it has finished, I get a black background, a layer with the shadows on, and annoyingly the color layer is just all black. Any idea what might be up?