This demo, unless i'm missing something, is literally less than 2 minutes long. It took me less than that to get all the hidden objects in the one room. Then I hit "leave," assuming that would take me to the next level (the only other option is "restart"), and instead if throws me back to the menu?...

https://steamcommunity.com/sharedfiles/filedetails/?id=3482407146 It is not anywhere in the image. Certainly not where it's pointing to.

Like the title says, not sure if that's the end of the demo or not.