Isn't there a programs that will capture screen writes at the hardware level?
I have tried several Firefox add-ons, and several stand-alone programs, and none of them will save videos from this site. I even paid for Replay Media Catcher, and it didn't work, so I got a refund. (The website for the best Firefox video downloader I have, Downloadhelper, said Replay Media Catcher worked with that site.)
I have a slow internet connection, and cannot watch videos smoothly unless I can cache them. This site (4tube.com) doesn't cache, when you restart, it reloads, when you pause it stops - so I need to be able to save the videos to be able to watch them.