Excellent effort; I liked it a lot.
My first playthrough must have glitched, because I got the water and power sorted out, but no lights or final door.Another playthrough was successful, though.
It's got a creepy atmosphere without jump-scares and gore, and I enjoyed the exploration. I'd like to see a full-on game developed from this, continuing in the same atmosphere. It's got a similar vibe to Dark Hope, which I enjoyed immensely: A mysterious location of unknown purpose; puzzles that fit the game setting; exploration, etc...
(Full disclosure: Dark Hope contains number puzzles which are not base-10 such as we use daily, which I do not understand well.)
Church Of Stratum is exactly the sort of game that gets me involved, and I look forward to a fully fleshed-out game based on this prologue.
Good stuff, Tillion!
EDIT to add: I just contributed via the download link, but could only increase my contribution to $12 US. I wanted to make it $15 or $20, but the Itch.io portal didn't let me.