So my idea is a sort of hybrid of Maze Runner. We would start with a handful of kids (I really don't have a preference whether it's all boys or boys and girls. Actually I would probably prefer some of both.)
This would be during the early stages of the Maze Runner. There are a few kids, up to maybe a dozen or two. Remember that Thomas doesn't actually enter the Glade until the 3rd year. We would be able to sort of see how kids would react with each other, how they would set up a system to survive on, or not. Kind of like a closed area experiment. At least that is what I would call it.
I very much doubt that we would ever get to the point where the kids try to escape, but we could show them being confused about the maze, first encounters with the Grievers, questions about the elevator, ect. I might also add a few new fun loopholes and such to make the RP a little different and exciting.