iTunes download had been spotty these days, I was downloading CoPilot Live North America update around 1.34GB and the bottom dropped out on me for the whole day. What I did was delete the download queue from iTunes, quit iTunes and restart it back again. The update restarts itself and this time I get better download speeds. Try that, it may work. Yours is only 409Mb, and should make it a managably quick download. I had to wait 3 hours for mine to finish.