While I'm trying to learn this game, I found that I can't do ceiling clip with the chair in train job. I remember I did it easily even in my casual playthrough, but now I can't. :( What specific input you need to do the ceiling clip?

Another question is that while I was playing with this game, I found this glitch. Is it already known? It would be only minor time save or might not be useful at all but just posting it.

I believe it's because you are releasing the mouse button after you pick the chair up. It should work if you continue hold the mouse button down, doing that should allow you jump and climb on the chair to go through the ceiling.

I do know about object boosting and there is 2 situations that it is useful. 1 of them I try to already use in my runs

while the other is more inconsistent and i can't do it properly

thanks for the reply! currently I've learned almost every levels but I can't get the skip at Bergamot Tower level, that you go OoB and go straight to shop using the deck. when I get the deck and try to launch myself into the shop, I don't get enough distance or launch into wrong direction. Is there any specific setup that makes this skip consistent?

The first thing to realise is the beginning angle of the deck. It is at the perfect angle to use to jump in the direction you want. That way that I understand the jump is that it occurs when the deck hits the ground and depending on the angle of the deck will make you fly in that direction. So the way I do it is take the deck and right as it hits the ground I pick it up while having my back facing the wall I want to fly through.

That is how I think about how I do the trick. (you can use youtube to slow down the speed to see when I pick it back up).