I think demo should have a stronger cliff hanger as an ending. Currently I'm not even sure what's the significance of what Teresa did. Was it even a big deal? Did Teresa start some chain of events? Did something change about the island or people? Did she attract attention of mysterious forces or something? Whatever happened feels too vague to leave me wondering what's gonna happen next.
The graphics look very pretty and well made. The sprite animations during VN parts look nice and dynamic. Everything feels very polished and high quality.
The gameplay is really absorbing, especially the puzzles. I got all stars on both levels. The ability to undo during puzzles makes it really fun and spares a lot of annoyance. Can't say much about timed challenges because I don't feel skilled enough yet to enjoy them properly.
It'd be more convenient if exiting a puzzle opened the page of that puzzle. After completing level 2 I still had some stars to earn on level 1 so I had to manually return to page 1 each time. I imagine in full game with more levels, having to click through multiple page could get annoying.