Again, technically I think this fits the rules, but in the spirit of stretching yourself, CHALLENGING yourself, then a photo taken specifically for the SNAP: you selected would be better. But I am not going to quibble about that :) Really, it's a balance. The aim is to get you challenging yourself and creating!
And I did say you can use a previously created layout for any of the challenges so is it that you are using an already made layout, that wasn't made for one of the challenges?
Certainly for any of the OTHER categories, there isn't any question - new, old, previously scrapped or not, any photo (except one you grabbed from the internet for example!) is totally fine.