I'll be honest, I haven't actually finished the demo yet (I can't find the door I have to unlock with the key from Haskel's room or whatever his name is), but thus far this seems like a really solid foundation. I'm intrigued by the potential for the story and combat, although the enemies so far have been way too easy. I also wish that the main character moved a bit faster. Maybe add a sprint button that consumes stamina over time? I can't think of any complaints beyond that, and I'm very excited for the final product. Don't give up!
[POST-COMPLETION EDIT] Alright, having finally finished the demo, I can give some more definitive critiques. I still don't have much negative to say that I haven't said already; the player character walks frustratingly slowly, and combat is kinda boring. That's pretty much all the bad stuff I can think of. I'd say my favorite parts of the demo were the forest town of shadow people and the Loser Room. Those two areas have some high-tier atmosphere, but in totally separate ways, demonstrating the flexibility of the developer in this regard. I'm also excited to see the story unfold; the little that was revealed in the demo got me really engaged. Like I said before, keep up the good work and don't give up.