Heh, mine just arrived in the mail today.
Basically, have the adjustment screwed almost all the way on. The bubbles should only come up to about the middle of the upside down V-nozzle in the collection cup. Since its brand new I'm not expecting it to skim much but after about four hours of running I had dark-tea water collecting (about half a centimeter, we'll see how much it collect over-night).
I had microbubbles for about two hours but it wasn't as bad as say a regular Prism skimmer. This thing was a breeze to setup. Bubbles went away after about two hours.
So, my suggestion is, screw the air adjustment nozzle back on - letting too much air in lets all the bubbles and water flow freely -- this is not the objective. You want the dirtiest stuff to collect and spill over the top.
Anyways, good luck with yours!