nanoDLP

I'm working my way towards a homebrew vat type printer.
I have nanoDLP installed and running on RasPi, and test motor driver sketch running on Arduino UNO, stepper motor works.
From what I have read here, it seems that all the hard work is being done on the nanoDLP side, and all the stepper motor control hardware/software needs to do is accept commands from the nanoDLP software.
Is there more going on in the GRBL or Marlin firmware than I think?
Is the Adafruit Motorshield v2.3 a decent candidate for this build? I know that it is capable of driving the stepper, and it seems to me that the sketch / firmware on the Arduino Uno could be pretty minimal; needs to accept commands to move Z axis a certain distance (number of steps), and acknowledge the state of a limit switch for homing.
Does anyone know of anyone attempting a similar setup?
Or should I just go with the flow and run a Synthetos G-Shield and the grbl firmware? This seems like total overkill to me, as I'm only controlling two steppers, one for Z and a shutter.

Where can I get info on the commands that nanoDLP is sending to the motion control hardware?

Thanks,
Cyprian.