I've been wanting to do this for a while. I've done several simulations, but I finally had a chance to make some molds using it a few weeks ago. The "arms" are a simple flat surface, but the "body" has a 3D contour.
1. I used the outline to create a single depth pocket using JK's Trochoidal milling method.
2. CamBam didn't seem to want to convert it directly to geometry so I created an NC file, and the used that to create an NC MOP.
3. The NC MOP was easily used to create geometry into an empty layer.
4. Then I exploded the geometry and used the select by type plugin to delete all the lines.
5. I mapped all the lines to a surface in a new new empty layer.
6. Finally I created an engrave MOP to cut the lines onto the surface. Or rather I used them to cut the finish pass to the surface after leaving some roughing clearance in the preceeding roughing operation.
The mold itself is really nothing special. Its just a finish texture I have been wanting to do for a while.