Plug the SD card to the Raspberry Pi, and connect it to the display with a HDMI cable, and power them separately. Connect the Multi-Control to the Raspberry Pi with Mini USB cable.

After rebooting, you can see such a page on the display.

There will be a prompt for you to set the controller.

Since the driver of the Retro Game Box has not been installed yet, you need to configure your USB keyboard first. Press and hold any key to let the system confirm that you’re using the keyboard as the controller. Set the key mapping in the menu popped up then. Please refer to the Key row above.

You can set the extra buttons randomly by yourself.