I'm trying to make an AMV, so I downloaded some videos with the Free Youtube downloader. I tried importing them to Sony Vegas, but there's no video, only audio. The only options they have for the free Youtube Downloader are MP4, AVI, and FLV. The videos have worked on Sony Vegas before, but now they won't. Regular videos that are uploaded from an SD Card work on Sony Vegas, which are AVI as well, but downloaded videos won't. The videos work in Window Media Player.

Help? D: