Assembly board ...

solder all components

Burn bootloader ...

it is easy, just connect atmel ICE,

run arduino IDE and click on ...Burn bootloader

Now you have Arduino zero compatible board, you can upload display test demo

Install Circuitpython ...

Download circuitpython release

circuitpython-arduino_zero-0.9.1

rename file to firmware.bin

press twice reset button to activate bootloader

run this command

bossac -e -w -v -b firmware.bin

press reset ... now you have new drive in computer ...

copy main.py file ... RGB LED start red flashing :)