I agree with Storm that there is a fine line between nothing new under the sun and a novel concept. Is there a creative way you can accomplish some of the same purposes with flashbacks or chapters alternating between the current and the past?

Again, you have to decide what the purpose(s) of this layout is. Good luck as you continue working through it--perhaps the remainder of the Prep exercises will help you iron it out. I know some of them have helped me as I worked through some similar issues with where to start and how to communicate both my character's backstory and the current events.

Let it roll around in your mind for a while; it'll come to you.

Best wishes,

Amy