Climbing up does not work for me. Up and W will only make the PC jump. When on a ladder and attempting to climb up it makes the climbing noise but does not actually climb. Using Chrome Version 35.0.1916.114 m. Climbing down works fine.
Otherwise the controls feel a bit slippery (as others have said) but may or may not be a good game, I can't tell because it doesn't work well enough for me to even interact with the first enemies.