I spent the morning wiring up a test rig to see if I can get the stepper to turn
Been there, worked fine indoors as a trial but when i set it up on the machine nothing...... 1/2 hour of head scratching and I realised I hadnt done the driver test for mach to take over windows, as usual operator error....lol

Anyway back to your machine. Over engineering is fine but there are a lot of redundant parts in that design, before I stick my oar in I need to know a few more details

Are you using the skatebearing arrangement, what are you cutting, what is the power of your motors and what are the sizes of the 8020?