Sorry for the wait! Here it is, a spoiler-free version:

* Read the notice in the main hall, and then the Holy Scripture.
* Find the key to the top left corridor in one of the flower pots.
* When you are in the corridor with the five rooms, each room will quiz you on something in the Holy Scripture. The answers can all be found in the Scripture in the main hall, which will have all the lines from the Book of Creation.
* Once you have unlocked all the rooms, read the children’s books in each room.
* Arrange the page in order to get the code to the staircase. Storage Room 3 has the first page, so the first number is 3. Storage Room 2 has the second page, so the second number is 2, and so on. The rest are pretty straightforward.
* Unlock the door and go up the stairs. After the cutscene, skirt around her and run back down the stairs.
* Go back up the stairs, read the Scripture, and unlock the door with the key you can find in the Scripture.
* Go into the music room and read everything you can read.
* Go back outside, and examine the Scripture on the floor to find a diary page.
* After the cutscene, just keep going forwards and don’t look back. Walk down the stairs, facing forward and not looking anywhere else.
* In the corridor with the five rooms, keep walking straight. The Scripture is blocking your path, so just burn it as fast as you can, and get to the main hall.
* Once you meet the new person, go back up the stairs. When you realise that the door is stuck, and your friend suggests to find something to break it with, say no.
* Go back into the music room and read the letter.
* Leave the room and look at the back of the first diary page. Remember the letter you see on it.
* Go to Storage Room 3 where you found the first page of de Lancastre’s drawings. Search the bookshelves for the second diary page. After the cutscene, examine it again. Remember the letter you see on it.
* Go to the main hall and check the suit of armour on the right. Search it for the third diary page. After the cutscene, examine it again. Remember the letter you see on it.
* Go to Storage Room 1 and examine the lamp for the fourth diary page. After the cutscene, examine it again. Remember the letter you see on it.
* Go back to the music room. Remember Chapter 2, where there was a door in the room? Go to the exact spot on the wall where you remember the door being, and search for a hidden door.
* When you’re in the Forbidden Room, search the shelves for a staircase key.
* Go up to the top-right for the safe. The password will be the four letters you found from the diary pages. (ANYU)
* Once you get the report, use the staircase key to go upstairs from the music room. Keep going straight until you reach the balcony.
* After that, you will have one last cutscene.
* In the final corridor, just keep walking down and don’t look left or right. Talk to de Lancastre, and then read the book you find at the end.

Gonna post some Chapter 4 updates soon as well! :) Stay tuned! Also, I’ll really, really really appreciate feedback and thoughts on the game, so if you have any, please leave a comment! :D