That was superb! The graphics were adorable, the music and sound effects were spot on, the theme was delightfully off the wall, and the challenges escalated at just the right rate from level to level.
Hard to say what could be improved, except that it might have been fun for the cowboy to have a temporary acceleration move mapped to the other button.
Also, it was a little odd that I had to deliver the cows to the train engine (rather than to the cattle car)...