We've prepared a guide for the demo in case you get stuck or just want to find all the secrets more easily: Mystery Guide + Tips.
V26
Added more sound effects throughout the game.
Using luck to improve your odds now appears as a separate choice rather than a mode that gets toggled on/off, since it was easy to miss the toggle button.
Added The Book as an item that appears in your inventory as well as making how to continue the mystery more explicit in the journal and item tooltip.
Added the option to talk to Leena for tips and reminders to the main activity menu.
The first event of "The Hole" mystery has been expanded slightly with an extra visual and more choices.
Title screen now has a few variations that are randomly selected.
Time of day icon has been expanded to make it more noticeable.
Added more time variations backgrounds to the following locations: Abandoned House, Gym, Library, and Antique Store.
Added a new Leena animation to the end of the demo (start of summer).
Steam Deck gamepad icons have been adjusted to look nicer.
Failing to investigate a location now has a visual.
Various small art adjustments.