Would it be spoiling the fun to talk about the secrets and how to get them? (Or would discussing it be half the fun!)

I got all the achievements in Morning Post, though I'm not *totally* sure how I got out-of-bounds tbh...

In Library, I've seen the cool stuff you can see in the sky when you jump high enough for the camera to clip the ceiling a little, but I haven't figured out how to actually GET out there, not even by building a mountain of books to try and physics myself through the ceiling...

I've found a secret room that looks like it has a little gap to sneak through, but I haven't figured out how to get through it...

I've found multiple locations of the two friends who move when they get books, including the one in the secret room, but eventually they stop coming back...

I've noticed a bunch of little things that look suspiciously like diagrams, including one in the secret room, but I haven't figured out if they actually mean anything...

I've tried opening and closing doors, even from a distance, but I haven't found any trace of the Door Wizard! I can't figure out how to get the permanently-open door in the left half of the library to close, either...

Anybody stumbled into more yet?