Dessign Exhibition Theme help needed

I have recently switched my site to the Exhibition Theme and have just about everything in place, yet for the life of me I cannot figure out why the Feature Big, Feature Medium and Feature Small functionality is not working. I have followed Marios Lublinski’s video set-up tutorial and still cannot get this to work on my site at http://sumofallmoments.com

If anyone can help me out, I’d greatly appreciate it as I cannot find anyone/anywhere that offers support for this theme.

Thanks,
Jessica