Excellent submission!
I played it through the end—what a twist and fun final puzzle! The voice acting and sound design were a delight! Beyond our inner monologue, I appreciated how it trusted me with its puzzles and barely held my hand. The atmosphere was unsettling, but the whole package kept this weenie glued to their seat!
The custom audio engine is solid. Perhaps I find the reflections to be a little bright, leading me to confuse the doors being in front or behind? I often wished the rooms had more flavorful sonic details to tell them apart, mostly to prevent me from feeling lost. For example, maybe there’s a leaky sprinkler or electrical sparks somewhere in the ceiling of corridor one? Hearing that would help orient and further immerse me.
I only encountered one gamebreaking bug which forced me to Alt+F4 and continue from my last save a few times. Either the audio crashed or I got stuck in a wall—it was hard to tell exactly—but the controls went unresponsive. Perhaps I was tapping my foot too often?
The minimalist graphics are effective and don’t need changed, but I would suggest a minimal UI for the title and menu screens. Perhaps a settings screen, controller support, and haptics would be nice? That’s all that I feel is missing from this for it to receive an official release.