1. I just realized that with leftovers you can do a kind of "speedglitch" making you go faster, saving approximately 2.X seconds, BUT this also works with the garbage from the first task, but it saves super little time, I couldn't find a way to know but if we combine everything it could be 3.5 seconds saved

2. I also discovered that for the windows, the last one specifically where the monster appears, I can close it through the wall :)

EDIT:

I realized we can do the same in chap 1 we can do the same with the garbage and the broom