There seems to be a 1) fundamental misunderstanding on my part or 2) a fundamental element missing in this software - the concept of scene as a grouping element in the timeline. I was trying to use VS for semi-technical explanations of software flows & integration - a situation needing lots of elements across multiple scenes. At some point the timeline became unmanageable (e.g. needing to add elements to early scenes was really painful).
Is there a way to handle this (other than simply making multiple scribes)?