@Mar Going out on a limb here: Are you sure you got the names of your scripts and their locations right?
You’re talking about ‘startMagicMirror’ which could either refer to what I called ‘/home/pi/start.sh’ and ‘/home/pi/startMidori’.
In the response you’re getting from your Pi it is referring to Electron, the browsing environment used in the default MM2 system, but which sadly doesn’t work on the Pi Zero. Running MM2 in server only mode would eliminate the whole of Electron I think.
Possible solutions from the top of my mind would be to check your names and paths, and to make sure the ‘start.sh’ script is an executable by using the ‘chmod a+x /home/pi/start.sh’ command, again, names and paths could differ.
This MIGHT also solve the connection refused issue, but I doubt it, for that we might need some more info
Edit: On a side note, I thought I had commented on your question like yesterday, but silly me didn’t press the ‘submit’ button, sorry!