Not sure what you call the feature, but on the demo page I can click on different K2 categories from the submenu, and the items transition and move around. On my site, the whole page just reloads. How do I set up the submenu to get this sort of animation?

Does the submenu get placed onto one of the K2 items? The template demo shows the submenu underneath the mainmenu. On my test site, they are side by side. I'd like to give this template a try but can't find any good documentation on how it gets structured properly so that the category-change masonry animations occur.