Come to think of it, the expert one would be the most time consuming (except the mental). I'd like to have a go at it, but I'm not sure I have the time.
erdelf is right, you need to have only worked on the game this month in order for it to be in the challenges.
Edit: Every challenge scenario, whether it says so or not, has to be completed the month the challenge is created.
JetLennit, I was wondering, when you say "you can't ask for help in the discussion section", do you mean you can't ask about anything you're going to have in your scenario, or you can't ask about the specific challenge, such as "role playing", or "scenarios without actors"?
As it turns out, the expert challenge is not as easy as I thought, and I won't have it done by the end of the month. I'm also not sure how to define a role-playing element in a game.