@moorepants As for the requirement for names: what if the name is an optional argument for VFrames; it's default value is `unnamed`. But say then a `Scene` requires all its VFrame's to have unique names; so when a VFrame is added to it and its name is `unnamed`, Scene changes its name to `vframe1`, etc; it has a count of how many vframes there are and ensures each VFrame has a unique name?