okay I played version 0.1.1 through to completion. Despite the game's simplicity, I found it enjoyable. It's definitely inspired by the likes of Slender and Granny, but that's okay of course.
I don't have any harsh criticisms because it's a demo release, but I'll say sometimes the AI is a little wonky. I've stood right in front of her and no reaction until I get pretty much in her face. other times she saw me through the wall or floor and entered her chase mode. Luckily she never actually found me then. The actually death jumpscare is okay, but it really gets you once or twice. Maybe add in variations based on where and how she gets ahold of Mario.
To end it on a positive note, I enjoyed the little attention to details and the exploration factor. The progression milestones even somewhat match the OG Mario 64 game(which admittedly I'm hazy on because sadly I never got to play it myself). And one of the more eerie things is hearing Peach utter a soft "Mario" occasionally when you jump in a chest. Rather spoopy.
In short, it's a beta game. Don't expect much JUST yet. But despite this and with this in mind, it's rather good. I see potential and want to see where this will go next.