I think it is an unwise decision to have the camera obscured by the mod. If it is intended for people to have the mod on most of the time and then remove it if they want to take a picture will create problems as to what they do with it. I take off style shells to use the car dock and use the other mods and the question is always "where to put them".

Is it your intention to have the mod be used while standing up or will it be used when it is resting on a surface, like a table or your lap? I would hate for the mod to come off from typing too hard but the magnets are really strong and that is less of a problem than it might seem.

Your mod seems more traditional than the other keyboard mod in the challenge and if you are a finalist then I am sure motorola will help you with your design as they have already built a slide out keyboard with battery but it was internal use only. Moto Mod concept to product

For those who are ambitious, why not create a "sailfish mod" where you slap on a processor and have it run an app that launches sailfish and it can access many of the resources of the phone?

Anyhow, good luck and I can't wait to see your product and will probably buy it.