It took me less than 1.5 hours.
As already said the cathode wire was to short and I had to find an other wire that has more or less the same sice.
In
addition I was a little bit confused, because there were more
stand-offs in the kit than needed and i thought I forgot something.
Also I tryied to put in a 18650 protected battery with a button top positiv pole into the metal holder. The batterie was to long and the holder were bend outwards. It was that bad, that i had trouble to put the boad into the pelican case. I have orderdn now a protected 18650 battery with a flat top positiv pole. This should work way better.
As information for the other builder:
If you fire up the Zen without firmeware on the M5Stack it just shows a white screen. Sounds logical after i think about it.
I
had additinally the problem, that my usb port on the PC delivert not
enough power so the M5Stack crashed repeatatly during connection with
the M5Burner. Changing the port solved the problem.