Bobby is right. There should be a rubber ring around the collection cup. You can adjust the position of the rubber ring so that the collection cup sits higher or lower. At the low position, it will collect a lot of wet skimmate (clear, runny). At the high position, it will collect a lot of dry skimmate (dark, thick). You want to try and get dark skimmate so take the next few days to adjust the position of the cup until you start getting dark skimmate. It can take up to a couple weeks to break in, so be patient.
As for the preskimmer, there are different ones for different types of pumps. Each box is made to fit a specific pump. I was running a Rio on my Remora, and it was HARD to get that pump into the preskimmer box, but it did fit. It might take a lot of wiggling to get it to work. Or maybe you just have the wrong box for your pump.
