For the first cutscene, you can easily skip it by loading the save after the cutscene. And for livesplit, there isn't really a way to see it in fullscreen unless you have two monitors. You can either play without seeing it or play in windowed (I recommend the 2nd option since the game tends to crash when you alt tab in fullscreen).

If by crouch sprint you mean baby legs, you can do it by being fully crouched and jumping to a higher place. You also don't want to crouch when you land or it will cancel everything.

So for example if you do this after male ward boostup, you would crouch after the boostup, wait a little bit, jump to the other side and stop pressing crouch.

Also this is only a visual glitch, you have your POV as if you were crouching but you still have the same hitbox.