HS Freezes and Grays out

I'm using HS for both a taxonomy and node reference hierarchy. Whenever either the taxonomy or node reference has a child, the hierarchical select field turns gray once I select a parent term and it loads the children for it. I can select a child, but it's grayed out and then doesn't allow me to save the content. This thing only happens when there's a child, and it happens for both taxonomy and node reference. Any help is appreciated!