I think this is ok. Under the Fair Use Act, it isn't copyright infringement to display a copyrighted work for purposes of review, education, parody, criticism, etc. Though, some companies are very restrictive about their work being displayed and report any potential copyright problem to YouTube, who're demanding you to desist. If so, it's probably easiest for you to just remove the video and forget about it. On the other hand, Revolution Software is providing the game as free download, so there shouldn't be any danger form this site at all. Anyway, be careful not to use any third party music, because the chance to get into copyright issues is pretty high in this case.