I'm not sure whether to call this 1.2.1 or 1.3, but here is the update anyways.
Apparently Shadow's ability breaks due to me tampering with the forwardmove and sidemove variables (the easy way of doing this), so I decided, I would just translate the game's C code relating to movement, into Lua. Now it should be more accurate than ever!
Short version: I copied the game's code to double air movement accurately.