I made this script that does a pretty good job of downloading all the videos through the web interface (only tested so far in firmware v1.00 and chrome v49), just navigate to the sd card menu and copy and paste the script into the javascript console (ctrl+shift+j in chrome, didn't tested it in firefox or IE yet).
I did notice that the tab can't lose focus (screen saver, opening another tab ect.) or else it will download duplicates or miss some files. There are two variables at the top of the script that control timing, if it is pausing to long between folder changes or the videos are taking to long to download then increase or decrease those values. When you paste the script into the console and press "Enter" there will be more instructions, make sure to scroll all the way to the bottom before you start, they might be hidden.
I hope to be able to test this on newer versions in a few weeks. So far it is working really well.
https://gist.github.com/anonymous/55b41ba3130c101017048f05aa989434