Right now, the fix is simple. You need to take all the files in your game's "backups" folder, copy and paste them over all of the game's "files" folder, and reboot the game and disable all mods. Then restart with an empty mod loader and reload the mods.
Couple things that may help after that:
1) Make sure that the mod's folder name is "AricsExpansion". I had a version uploaded temporarily that was named wrong and it will break, the current link is good.
2) The mod will not work with Constants. Immediately breaks. But as Constants is pretty much just an example mod, shouldn't be an issue.
3) This mod will work with Random Portraits and Delayed Loading. It probably won't work with any other mod, as it's becoming a very extensive overhaul and touches a lot of parts of the game (and the game doesn't like itself being touched twice by mods, however it's done).
If the mod still doesn't work after, let me know if there are any errors in the console (if you're using a console), if you have it downloaded or are doing it on itch.io (I think itch.io works a little different and haven't tested, but the downloaded version works fine), and anything else. Walked under ladders, broke mirrors, whatever may help. We'll get it working for ya