Hi! So a few things
- The reason the field elements are made blurry when you're running sleep[] is because they're unlocked, so are greyed-out to indicate that they're not editable while sleep[] is running. For on-screen text that you don't want the user to be able to edit it's neatest to set the fields to "locked" (Widgets->Locked when they're highlighted), that way they won't grey out when input is locked, and users won't be able to mess with them.
- In terms of adapting the eggtimer contraption, you'll likely need to edit the prototype of the contraption, if you go File->Prototypes you should be able to get to it. Probably what you'll want to do is change the "click" event into a function you can call externally, there's a bit about how to do this in the Custom Attributes section of the doco. Then you'd probably want to call this as part of the button that switches the user to a new card.
- I would probably be inclined to roll my own code rather than using a contraption for this, to be honest. Probably I'd use a hidden slider set to "animated", which means it'll run its own "on view" function every frame. Then in the "on view" basically I'd have it increment its value by 1 each frame, and then check when it gets to greater than equal than 180 (i.e. 3*60) and go to the next card when it does. And the button to move to this card I'd set to reset the slider to 0.
Hopefully this makes sense - I'm not sure how experienced you are with programming (especially in Lil) but if you need some more help I might be able to give some code snippets when I'm more awake and able to check that they actually work and such.