Adventure games I've played in the past have taught me to slap items on things at all times, and boy howdy does this game hate it when you try to use items on the wrong thing.
So far I've used the kitchen key on the locked door in the bar and gotten <null>, which let you dismiss it but just came back forever, and used it 2 other places (stuck door in hallway and food table in entrance room) and gotten the error message "If you see this god help you" which has you stuck until quitting to title.
I'm on windows and just downloaded it today. I figured I'd report this, but I am definitely taking a break from applying items randomly.
ETA: Yeah I've found several more, but IDK what extra details would help? The doors aren't identifying themselves when I interact with them keyless so I'm not sure if this is something that just broke or what