Hi folks, I've encountered a crash issue in my current playtest that I cannot seem to correct myself. I recently completed a full playtest of my game to verify that all of the eventing works correctly, and am currently undergoing a 2nd playtest to tweak the balance using Shoukang's Action Order plugin.
I've recorded a quick video to highlight the crashing issue.
To summarise:
The game crashes with a Type Error originating from rpg_objects when a fight ends and the game transitions back to a story map with the Action Order plugin enabled. It correctly loads into the map and has updated it with new event pages based on the switch that is turned on when the fight is completed, but crashes instantly when it should play a BGM file and make a text box appear.
Action Order has not been edited outside of adjusting the formula it uses to calculate turn order from Agility to Luck, and adjusting the amount of unit turns it shows on screen.
When Action Order is disabled and the game reverts to the default turn system used by SRPG_Core, the crash does not happen and the event continues as normal.
There are 27 other fights prior to this one where this has not been an issue.
Here are two screenshots, one of the actual crash log from the game, and one of the section of rpg_objects where the crash seems to originate.

If anyone has any idea why this is all of a sudden causing a crash I'd massively appreciate it - this version of the game is very close to being pushed for a public demo release and I would really like to continue using Action Order for the combat. If there is any other information needed to diagnose the problem please let me know and I can supply that ASAP.
Thanks in advance!
RPG
Edit:
As a brief update I tested a few additional things:
If the fight is concluded and teleports the player to the World Map with a copy of the cutscene present, it plays out correctly and does not crash, even with Action Order enabled.
If the fight is concluded and teleports the player to a replica of the story map with only the cutscene present, it produces the crash.
When the story map is loaded into the first time, there are no crashing issues (probably obvious but I hadn't mentioned this yet!)