Okay, I've come back to working with the Inventory module after a long hiatus (it wasn't working). I disabled, then removed the module from the module manager, then re-imported it. That seems to fix everything and bring it back to square one, with the downside that it deletes everything I adjusted.
The issue now is that every time I use a custom inventory skin as opposed to one of the defaults, something stops working. I made the custom skins by duplicating one of the defaults and replacing the images with my own. Nothing crazy.
Currently, the "on drop" trigger has stopped working. With a default skin, dropping the key from the inventory onto the door makes the door open (I use the example scene to test). When I replace the skin with my own, dropping the key on the door does nothing. The inventory stays open, and none of the actions follow. I switch it back to the default skin and everything works.
I also noticed that when I create custom items to the inventory catalogue, they flat-out don't show up in the inventory. To make something show in the inventory, I have to change the name, sprite, and prefab of one of the default items. My game has dozens and dozens of inventory items to add-- what will happen when I run out of default items to customize?
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