data.raw["loader-1x1"]["aai-express-loader"].next_upgrade = "aai-extreme-loader"
-- This is the line that causes the issue. It assumes the express to extreme loader is coming from aai. Instead, a line, and any like this should be in their respective loader checks.
Also noticed that the mod assumes that the setting for aai-loaders is NOT "graphics-only". The built-in aai-loader maker silently does nothing if the setting is "graphics-only", and that setting WILL cause this mod to crash.
