This was awesome!
The visuals were beautiful, the interface was nice and straightforward, the sound effects were good and punchy, the music was fitting and eerie. Good amount of polish all around!
The levels were just chock full of little details on the walls and on the ground, I loved just looking around to see what there was.
The game also effectively carried across the horror aspect, even if it happened a couple dozen times I'd always jump a little at an enemy encounter.
The cutscenes were also well done, but I did run into a little bug/oversight. In the final cutscene where you go into collect the artifact, and enemy spawned right on that last tile. So for the entirety of the first-person perspective of the cutscene theres a little creature in the middle of the screen. I was able to blast if off partway through but it did spoil the tone a little I think lol.
As for the combat itself, wasn't very deep but I think it was adequate. Had enough enemy variety and punchiness that I didn't mind having only one weapon and effectively 4 actions the entire game.
It was unfortunate you couldn't get the actual in-game settings working, but I appreciated the steps to make the game fullscreen in the ini file.
My only real suggestions for improvement/expansion would be maybe letting the player use Williams' railgun as a weapon/upgrade and preventing enemies from spawning on tiles leading into a scripted sequence. also a nice little detail would be if your squad's status updated as you found them. Like if Williams' became listed as dead when you find her.
Besides that I really liked this one, great work!