No, they don't need a constantly running check. Think about it. The only time you should check for when you get all the numbers is the precise moment you enter a number, not a parallel event, it's extremely wasteful. And changing the display of the numbers only needs variables, not switches, it's hard to explain, but the events can change pages without needing a separate parallel event. You already have a variable, that's all you need.
Come to think about it... Wait for a bit. I'll make a prototype with my own version of a code puzzle and show you how it can be done better, without it turning into spagetti and relying on so many parallel events, and I'll send you a link so you can look. That is if I'm right... If I'm wrong I'll eat my words lol.