You can refer to the Manual on how the analyse components operate. Springs or zero length elements can be used to simulate joints between plates if you need to change the stiffness of the connection.
It would be simpler to keep them in the setup as simple polygons for the analysis, and the finger joints would only be important in the fabrication. The joints would not be necessary in the Karamba simulation as your structure acts as a dome and the joints themselves would not play a large role in the overall structure.By selecting all the points on the mesh at the line would simulate a line support.Can you somehow bake the breps and reference them in the file so that it doesnt rely on other plugins. Hi cannot seem to run your script as it gives an error at the Brep.