I get a very similar error if I’m just running at the CLI. With the GUI running NPM START (from a local terminal window) is successful, I never did get it going from CLI.

I also never got PM2 to successfully work without manually kicking it off after the gui has launched.

I’ve taken about 4 runthroughs at the install, so at this point I’ve no idea what the issue is.

pi@raspberrypi:~/MagicMirror $ DISPLAY=:0 npm start

magicmirror@2.0.0 start /home/pi/MagicMirror
electron js/electron.js

npm ERR! Linux 4.4.32-v7+
npm ERR! argv “/usr/bin/nodejs” “/usr/bin/npm” “start”
npm ERR! node v6.9.1
npm ERR! npm v4.0.2
npm ERR! code ELIFECYCLE
npm ERR! magicmirror@2.0.0 start: electron js/electron.js
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the magicmirror@2.0.0 start script ‘electron js/electron.js’.
npm ERR! Make sure you have the latest version of node.js and npm installed.
npm ERR! If you do, this is most likely a problem with the magicmirror package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR! electron js/electron.js
npm ERR! You can get information on how to open an issue for this project with:
npm ERR! npm bugs magicmirror
npm ERR! Or if that isn’t available, you can get their info via:
npm ERR! npm owner ls magicmirror
npm ERR! There is likely additional logging output above.

npm ERR! Please include the following file with any support request:
npm ERR! /home/pi/MagicMirror/npm-debug.log