Here are the demos that probably won't crash in some catastrophic way. I won't claim they're fully debugged but I'm not aware of a way to break them. These demos exist to prove that some degre of basic functionality works but don't resemble a full game.
One Room Demo (August 2017)
Very short demo that verifies all the basic game mechanics work:
Here are demos that might crash in some catastrophic way. These are usually checkpoint builds where I finished some big new thing but haven't debugged it or made any attempts at optimization.
Empty Mall Demo (February 2018)
At the conclusion of the "One Room Demo" scene the entire mall can be explored. There are no other NPCs in the mall and interacting with objects displays default actions & text. Exiting out the south entrance ends the demo. The main purpose of this demo is to verify all the scene transitions work.