It ran for about an hour, and made beautiful slots. Made a prototype in pine to make sure everything run accoeding to spec, and I'm glad I did as there were a few corrections I need to make. I'll need to better align the shapeoko, and then I can run this again. I also need to redesign the pattern - I think I can save almost half the time if I do that better.
Shapeoko 3 is up and running. I still need to calibrate it, as I'm getting a little drift in the depth (1/16" over 12"), and the x/y slots came out at an angle (but that might be my material not being square to the machine - need to measure).