I use 1/8" tapered ball nose bit at 9% step over. After much experimentation, I finally settled on this procedure. I construct the frame and panel door using standard frame and panel construction, with the one exception being that the panels are the same thickness as the frame. The creation of the overall scene and then breaking it down into individual panel tool-paths was again a process of experimentation until I found a procedure that worked quite well. I don't use a roughing tool-path as I found just using a finishing tool-path at the the 9% step over was quite adequate. The maximum depth of cut is no greater than the depth to panel tongues that fit into the frame (making the assumption that you understand how frame and panel doors are made). No pocketing tool-path is needed.