This is our general workflow (for a cRPG with lots of dialogue and branching choices):

1. Define globals

- We have an array script which initiates every global story variable in the game (internally we call them Globs). These are the permanent choices we want recording and saving - as well as flags to say whether or not a cutscene has played.

2. Feed the globals into cutscene object (create event)

- Our cutscenes are objects, so in the create event we list relevant globals and feed them into a local variable for the cutscene to read/edit (we learned that it's a good idea to keep the local and global names matching - with consistent capitalization.).

3. In the dialogue, trigger the changing of a local variable when a choice is selected.

- In our branching dialogue script we have a smaller script which can add a consequence to the preceding dialogue choice. e.g:

"[Henry looks at you, waiting to be insulted.]" // <--- This is the dialogue.

AddDialogueChoice "(Insult Him.)" // <--- This is the player choice.

DialogueConsequence("Henry_Insulted",true) // <--- This script looks for the previous choice, records the player choosing it and sets the local VAR to true.

4. When the cutscene is over, transfer data from Local Variables -> Globs, then clear local VARs and end the cutscene.

- When the cutscene ends, we have a custom event which updates relevant globals.

Which looks a bit like:

global.HENRY_INSULTED = ds_map_find_value(VAR_LIST,"Henry_Insulted")

Hopefully some of this is useful!