Ok, I finally did read your walkthrough for endings 4 and 5, and the solution to get "true midnight" kinda blew my mind. :D lol. I probably would never have guessed it because of the following confusion: I previously thought the pizza was being delivered at ten o'clock - so two hours before midnight - as the pizza girl literary said the delivery will be "in ten", guessing it was a translation error and had to be "at ten". So I tried to guess after how much time it would be midnight. However, now I realize her text should have been: "in ten minutes"!
As for ending 5, I could have done it without the walkthrough if there was a seperate (object) text for the hands on the "object". (Trying to avoid spoilers here.) Then when I got the "thing" the cannon came to my mind, but did not fit in the slot. I did not knew that you could look outside the window in the cannon room, so unfortunately, as so often with these games, I resorted to the walkthrough again for the very last thing to do in the game. :-)
I also have a suggestion for the "ox room", for the hearing impaired and it also should clarify a bit more what happens: Maybe you should make it so that, when you stand on the trigger tile, you can show it being pressed down a bit. (With a different graphic.)