Hi Janet,
I checked with Justin on potentially using CSS via Resources to add the snapping such as what is discussed on this page:
He said that this is not something we can officially support at this time, but on his first reading of this, it seems to work on sibling relationships.
He said that with the scrolling frame, everything has to be in a parent group. So you would likely need to target the items inside the group, e.g., .scroll-vert > .group > *
