How to download your craftsy classes: on your main page you will see a tab on the bottom right that says 'Off Line'. Click it and you will see all your classes. The classes are broken up into segments. You just click on one of the segments (or however many you want to do at one time) and it starts downloading that segment to your hard drive.
It's awesome for those of us with satellite. The last time we flew I brought my iPad with all my downloaded classes and watched them. It was so nice and the time flew by. Haha!