Unable to download Youtube videos

Hi. I've been having difficulties downloading youtube videos since yesterday. Whenever I click on the download link for the video, the webpage is unable to find the filesize for the video and cannot download the video at all. I'm currently using Firefox version 22 and have the Savefrom.net helper 1.82 addon extension installed as well. Hope you can help. Here's a sample of the webpage of the video: http://www.youtube.com/watch?v=0SSmVNQpXss