I finally connected the M1-ATX to a motherboard and it worked. I didn't need to connect the ingnition, but had to connect the J6 to the appropriate M/B terminal. I also could leave out the J6 terminal, making switching the motherboard by the cassis On/Off switch.
I also connected the green wire to the black one of an standard PC power supply and get it to start properly.
When making the same with the M1-ATX, it does not start (tested it with harddrive on M1-ATX HDD port), however. I had to connect it to the ATX terminal of the motherboard.
Does anybody know how to start the M1-ATX without connecting it to a mainboard. Connecting the green to the black wire does not work for the M1-ATX. What's about the Violet (+5VSB) and the Gray (PWR-OK) wires?
Many thanks in advance!