throatrake I could not get it to work in Firefox even after turning off all of my blockers. Something to do with the default blocking of javascript (didn’t look into it any further).
It worked fine for me in Chrome on a desktop. I think that if you can see “Drag out your” written under the Download button, it’ll probably work. Then just click on either “Download” or the down arrow and you should get a file named cardfull.wmv to save.
