File for Incra Build it system

I have used the Incra Build it System, and I really like it. It’s more accurate than anything I’ve been able to put together on my own. But when you buy expansion panels it get’s prohibitively expensive. Does anyone have a file for the cutouts in the MDF for the system to make a larger sled?
https://incra.com/jig_fixture-build-it_system.html