I'm pretty curious about what the rest of iminlikewithyou.com looks like. So, hopefully my contribution is useful:

I think I got all the way through the demo, in any case it is very frustrating. I think that the whole interface is insufficiently intuitive. Considering the fact that your target demographic is (often) non-technical families, I would reorganize the methods of interaction.

There should be a simple pathway for every task that hides irrelevant actions on each step. For instance, once someone uploads a set of photos the option to upload more should be hidden until the user complete modifying the photos or returns to a 'home' page.

You are facing some very serious competition. There is a lot of work to be done before you launch.

Frankly, if you need a tutorial for an application like this, your interface isn't good enough.