OHH nice, I thought that it just some kind of job queue on up and running machines

It's much more than that, it's a way of life 🙂
But seriously now, it allows you to use any machine as part of your cluster, and send jobs for execution from the web UI (any machine, even just a standalong GPU machine under your desk, or any cloud GPU instance any mixing the two together:)

Maybe I need to change something here: 

apiserver.conf

Not sure, I'm still waiting on answer... It might not be exposed to the configuration file. Give me an hour or two