I am trying to set up a horizontal scroll lower down on a page that is vertically scrollable. I have compressed the area to the width of the stage as well as enabled scrollbars, but it is scrolling the entire page horizontally - instead of just the group.
You can see this by visiting http://nbpgrp.com/ and selecting the “What” tab, and scroll down to page until the groups of images.
Looking at your document, I don’t see that any of the subgroups are clipping the content nor have the Content Overflow set to Scrollbars/Auto Scrollbars. You should be able to set that up and then will have horizontal scrolling for those groups.
Just be aware that those inner groups will eat both scrolling directions, which can put a pause to vertical scrolling. There’s new CSS properties upcoming that can solve this problem, but they aren’t widely supported yet.
P.S. As a side note, how are you compressing those files when uploading to Dropbox? They seem to download in a corrupt manner where the actual .hype document is placed into a .hype document folder.