Step 1: Design
Each piece was exported as an SAT file for the next step.
Step 2: Fabrication Toolpaths
Full disclosure, I am a developer for Autodesk that helped build this site. :-)
On the 123D menu, I opened the SAT file. Soon, it will be easy to upload STL files to the Gallery for this.
Then I defined the size of my stock. I used a piece of 3/8 inch ply that was lying around.
Creating Tabs to hold the piece in place was critical.
Clicking on the Toolpath tab, it was easy to make the toolpaths. The default jog speed and cut speeds are pretty slow. So I defined my own pass settings that move the bit at 3in/sec for jogs and 2in/sec for cuts.
On the 3D Print Tab, I showed the machine and simulated the results. Then "Save Shopbot Files" produced the files I needed. Actually, because the geometry is basically 2D, all I needed was the file Cutout.sbp.
Step 3: Cutting with the Shopbot
With the Tabs in place, it was easy to cut out the pieces by clicking "Load Part File" on the Shopbot software and selecting Cutout.sbp.