How to progress past act 3? (Spoilers for act 3)

[RedCervidae]

Hello, I could use a little help without story spoilers if possible, I'm a bit stuck... I helped everyone in their personal quests, talked and spent the day with Loop, know how to sharpen the key knife, found and made the bomb, found out about the King's origin via the article and asked him about it, found out and asked about time craft, found the diary and asked the King what Can't I Remember? and Where are you from?, found the secret room and library and also the passcode for two of the storage rooms in the House.

I'm not sure what else to do or where else to go? Could someone point me in the right direction for progression past act 3 please?

[Pawkt]

Most of everything that involved "gated" progression after Act 3 that is:
1) You have to speak to Loop (it's not very well done as the text is greyed out)

That's about the biggest issue with the game.

[Yamza]

Also stuck here.

[Fiona Kaenbyou]

Am I right in remembering the last plot cue you got was 'finding something similar to the King's plan'?

If so, you need to get your picture taken by the mirror on Floor 3.

EDIT: Also, before that, there's the sparkly diary in the House library that you need to interact with to figure out where the King is from.

[The Improbable Imposter]

Originally posted by Fiona Kaenbyou:

Am I right in remembering the last plot cue you got was 'finding something similar to the King's plan'?

If so, you need to get your picture taken by the mirror on Floor 3.

EDIT: Also, before that, there's the sparkly diary in the House library that you need to interact with to figure out where the King is from.

Extra thing: you can't loop back to floor 3 with all doors unlocked to trigger this event, annoyingly. you have to loop back to floor 3 (doors locked) which is silly. Why can't I just inspect the mirror...