Nice idea and pleasant art style. Music is rather annoying.
I got the goat to 700-something meters (and I envy this goat a bit, since this is not easy IRL to move up for relative 700 meters).
Had some technical issues (played a downloadable build on a Mac). At game start, balls appear and disappear, but are not rolling down the mountain. Which makes it a lot harder to avoid the blue ones (I hate those anyway, since they are too close to each other). And despite them not rolling down they still do hurt from bottom... Also when they move down, they are a slideshow - one turn in a few seconds or something.
But they somehow weren't broken for me all the time, so I could play the game for a while, until it hanged (I guess you forgot to call free/queue_free on the ball nodes).