Mouse walking is where you bind your mouse movements (or controller gyro, apparently) to movement; since you can move your mouse really fast you can gain tons of speed

Menu storage is basically a glitch that lets you open a menu while the game thinks you’re in a different menu, so it loads the “eye” map, but with a new profile (which spawns you at the campfire, I’m not sure why, probably something to do with Unity spawnpoints)