After lot’s of tinkering I finally got this to work on a Pi Zero W. I have answered a couple of people in the forum about this, so I thought I would put up a link to my github where I have put in each of the files I used.
I have also tried making a single installer script for Pi Zero/2B/3B; if you have both platforms and the time to do it, please run
bash -c "$(curl -sL https://raw.githubusercontent.com/ac2799/MagicMirror/master/installers/raspberry.sh)" from the terminal and let me know how you get on… I have tested on the Pi Zero and it appears to work fine but advice or feedback still welcomed.
Here is a pdf guide for the process.
Some people reported difficulties when installing over SSH. The guide does tell you how to do it headless too (TL;DR: use SSH to enable VNC Server using raspi-config && download RealVNC Connect && connect headless using RealVNC Connect/VNC Viewer)