I installed this plugin yesterday. I deleted the sample videos, added my own videos from You Tube, etc. Everything went smooth and looked great. I came back today to add more videos and I find yesterday's videos are giving the message, "Requested video not found or access denied". I added another You Tube video anyway. It gives the same message. I can click on the thumbnail of a video, it opens a new page and the video plays.
I've tried updating my permalinks, but that did not help. The page is at http://mark.niftywebdesigns.com/video-home/.
(There are 4 videos on the page, but only 3 are You Tube videos. The 4th uses a custom URL. It is the one titled, "2014 Ram ProMaster™ – Work", and it won't work at all.)