Since this game was made in Unreal Engine 4, if you hit ~ on your keyboard you can bring up the console. This allows you to do some commands, such as "slomo," which allows you to slow down the game. While it will probably not be allowed for speedrunning, slowing the game down [slomo 0.<number>] makes you get bigger cube jumps (since the game is running at a slower speed with the same framerate). Lower framerates, or speeding up the game makes the cube bounce much more. I have not yet found if it is possible to make savestates, however.