The Corpo section is actually the hardest part to understand, so I completely get why it might be confusing. Here's how it works: the real netrunners' gameplay is replayed on the screen in the top-left corner. The four buttons in the bottom-left are each linked to one of the mini-games currently active on the netrunner's screen. If you open the correct mini-game and solve it before the netrunner does, you earn points.