For your first game this is quite decent.
PROS +
Creative use of lighting.
Good use of interactive environment.
Nice dialogue and writing.
CONS -
Default SFX/Font and Windowskin break the horror immersion.
Elaborating on the above - The level design along with the use of lighting is decent. You kept the scope small and together with the lighting it melds well to create a good claustrophobic horror playing environment.
I like how you can examine pretty much everything and get contextual feedback - that's a really nice touch.
The writing and dialogue is nicely balanced. Done well, to the point and not overcooked - which is very easily done so good job with that.
The default sounds, font and windowskin are counterproductive to creating a fully fleshed out horror vibe. People often neglect this and IMO it is far more immersion breaking than just using the RTP graphics
To be honest I don't ever mind people using the RTP sprites and tilesets, especially for their first project and when used well (like it is here.)
What bothers me more is just using the pre-set sounds (you can literally just pick from the RTP) better sounding horror game SFX that would better lend to the vibe of the game.
You can also change the color of your windows even if you don't want to download new skins for your UI. Changing your font to something more horror oriented would be great too.
Overall it's a decent game, but it is just lacking it's own personal stamp at the moment to set it apart from other horror games made in MZ.
For your first game this is a really good effort. Interested to see what you cook up next :)