The Estlcam control software is only compatible with the Estlcam firmware which can only be flashed to boards with 8bit ATmega328/2560 (e.g. Arduino) or AVR64DB64 (new Estlcam boards) microcontrollers. I use a Nano on a custom shield and, IIRC, @Tokoloshe uses a Mega on an Open CNC Shield 2.