Parent not appearing as viewed (grayed out) when you go through and view all of the children.

I'm running into an issue with one of my parent items. The parent item doesn't contain a slide. It's just a 'folder' to be able to encapsulate 4 children who have other children. When you click "NEXT" and go through the slides, the menu is auto collapsing which is exactly what I need it to do BUT one of the parent items isn't being grayed out when you go through the children in that parent. What could I be doing wrong? I'm currently using the most up to date Storyline2 and Chrome on Windows 8.1.

Below is a link to view my program.

http://www.d-scape.net/og_working/NMG_Heroes/story.html

I also just tested in HTML5 and none of the parents gray out. Is this normal?

http://www.d-scape.net/og_working/NMG_Heroes/story_html5.html

Thanks for any advance.