Forget it. It used to be decent and now they ruin your video with an ad link to their program! Absurd. There are firefox add-ons that are not this intrusive and do not require $30.00US to remove. Look elsewhere.
This is a brilliant add-on for Firefox. It continues to be invaluable for me as I collect hunting and dog training videos. Very easy to use and downloads can be actioned and monitored from the icon in the toolbar.