HardKnot OX 4x4

I've starting my build modeled after the OpenBuilds OX Open Source CNC Router Build by Mark Carew. I have already received all parts and built the majority of the frame.

Here are some mock-ups I did around the house. My wife was a sport since I was so exited to receive my tracks after waiting a month for a backorder to be filled.



At this point I've built everything exactly like the SketchUp of the OpenBuilds OX 48x48 Aluminum located in the Details tab.

Now I needed a real space to put this little beast together so I cleared an area in the garage. I also decided to pack up the car and finish the build at Techshop.







Issue #1:
I can't get my Nema 23's to act reliably on any axis. My Nema 17 for the Z works on every axis fine. I can get the 23's to move by turning the pots way down but, it's still sputters. I'm using the 24v 20amp power supply and stepper motors from the OpenBuilds store.
Is it possible I have my Arduino loaded with the wrong firmware or that GRBL 0.9 is not compatible with the gShield?


Current Setup:
Electronics:
Arduino Uno Rev 3 (Make SMD Version w/o GRBL preinstalled)
gShield v5 from Synthetos
Software:
Grbl Controller 3.6.1 (Windows)