A few notes from my playthrough - I hope all the critique helps develop for the final release:
1. I believe the first chapter requires more tension and narrative, to ease the player into their surroundings. Apart from the initial exposition at the beginning, there's little information presented to the player in order to ascertain where we are, what we're doing and why we're doing it. At first I thought we were in Vera's office, which confused me as I didn't know if we were already in the victim's head or not. The phone call explains that we are, but I think it would help if #37 left notes directed explicitly at Vera - maybe with her gift you could explain this by them sharing a connection to find the killer's identity?
Following that, I think that we should really get to know more about the victim herself. I really loved the segment with the piano and this was starting to showcase her life - the player needs to empathise with her if we care about solving her murder. There should be more instances of this.
2. The jump scares didn't really resonate with me, unfortunately. I think this game could benefit with creating an eerie tension, rather than multiple jump 'gotcha' moments on display. One is fine, possibly with the woman coming towards the player when they open the door, but the others seem a little too forced. They seem a little all over the place, too - what's with the inflatable clowns?
3. Although I suck at platforming sections, I think bringing in the mechanic nicely balances the chapters out - although I don't think a 'potion' is required, just let the player jump from the get-go.
4. Don't think you need a stamina bar presented in the top-left of the screen. The player will know when they can't run anymore, no?
5. WHO IS THE NAKED MAN??? WHY IS THE NAKED MAN???
Think you've got a cool concept on your hands, just needs a little polishing here and there. Good job!