How do you achieve those rope boost ? I see that you get really fast after hitting some ropes and i can't manage to do it

Are you talking about the power lines?

yea he is

I'm really sorry for answering this late. I "took" a speedrunning break, one year or even longer, can't remember. Better late than never I guess...

The boost is pretty easy, just press the movement button in the downwards direction (controller stick down), but I don't know the controls on the keyboard. Still I hope you know which button I mean.