hmmm. I'll have to look into the completing challenge thing you mentioned since its one of the things that I assumed were bug free. If its not a bug then its making sure that nothing is particularly confusing.
You have a restart button, you can ser it on the controls. I'll put a tutorial pop in in the first room (like with the kick) since playing without knowing that can be annoying.
The sway, you mean the shaking of the camera like when you walk forward or the tilt to the sides when strafing? The strafing can be changed, its called Lean Amount in the options, the shaking cant, I'll look into it for future versions.
Question? What did you feel about the difficulty curve? Because I am very sure that there is a level in there that should be a bit easier and maybe show up later in the game.
I will eventually have to give a new look to the older levels, because not all of them have to feel like a final boss stage or anything in terms of difficulty.
Glad you liked it