I know this is a really old thread, but I just thought I might add my fix. I had the same problem (except my skill videos worked fine, the only one that didn't was the Talana dragon one). All I had to do was rename the original Dreamscene_End.wmv, copy a video that did work, and then rename it to Dreamscene_End.wmv. I used a kill video for the bow attack that stuns, and it worked perfectly. I recommend watching the original video before you rename it, since you're not going to see it in-game.