Arancino's Night Journey [Discontinued]

I’ve added a ton of quests for the Overworld and the Undergarden, and started planning the lore and quests for the Nether. I also absolutely need to fix some critical bugs caused by... I have no idea what. So, I’m sharing this beta file with you—please help me figure out why the game crashes whenever you search for items in Creative mode, save a world, or save the game, by updating, removing, or adding mods.