Okay I'm totally new to ANY dialogue system and only just got back to Godot (*Unity Refugee) so I'm basically a noob. Here's my progress. I wish there was a sample timeline/scene where we could see how nodes are added both INSIDE the timeline AND in the Scene tree. It's confusing bc they're called nodes both places but are not necessarily equal.
In Timeline "position" node, I rt-clk open script/code. I see the script is named "event_position"...leading me to realize Position is an Event (not a thing or a location like I assumed). Inside the script, first hash is: ## Event that allows moving of positions (and characters that are on that position). We don't want to move them, just get one or attach it to character or instantiate it or somehow bring it into existence, so someone somewhere knows there is in fact a Position 0. But maybe moving it into the scene is the same thing?
The second hash is ## Requires the Portraits subsystem to be present! OK! So in Scene Add Child Node pop up, I have 2 choices of gray nodes: DialogicPortrait and DialogicSubsystem. Since DialogicSubsystem is gray, and DialogicPortrait is also the same kind of gray node, I bet DialogicPortrait is that portrait subsystem of which the ## speaks. That said, I'm going to post and request someone give us a basic sample we can follow as a template to get started.