Everything sounds fine. Here's the deal with the cups, they're not entirely necessary but they provide an unsprouted seed with humidity(when you mist the inside of the cup), but they only need it before they sprout. As for watering, keep the cube moist before they sprout, from then on water as I've indicated previously, wait until the top of the cube dries between waterings. A fixed watering schedule serves people more than it serves the plants, though after a while(and a couple of grows) you'll just know when to water.