Thanks for the video. Just fixed the issues with the stealth segments.
About the unanswered plot questions, the game gives clues about what it's wrong with the town in several levels, like the first encounter with the cult. There are more clues about what caused the wrong thing in the nap cutscene and in the library if you choose to read the second book. The context about the player character is told at hte ending and in the game page's description, they don't have much of a personality to be honest. They are basically another instance of the silent protagonist cliche.
I'm not sure about the game needing to tell you to remember the facts for the quiz, all you need is to pay attention to the character's dialogues. I'll consider changing this if I get more complaints about it.