Hi bwtr, Shadow Pass is used at the top level of the shader tree. If you go to where you select Multichannel, you'll find the Shadow pass option there. Essentially it's a "hide" feature that still allows a shadow to be cast from an object. This is a nice feature to use when blending photographs and 3D in Carrara. Spokes is typically used as a blender with the Mixer feature in the shader tree. (However, I've used it the Alpha Channel quite a bit) It can be animated over time. In the color channel you can make radars, clocks, propellers, hypno-beams... Mark