I’m using a 24V DC power supply, so I can’t miss 🙂
If using USB, everything seems to work fine, including web interface (except valves, not tested them yet). I’ll take another look at it tomorrow, just thought this might be the same setup + problem as requenym’s (except I’m using a DC power source) and was curious about what solved his.
I’ll post what’s wrong when I find the problem.

PS: suggestions where to look for mistakes are welcome 😀 Thanks.