I posted in the other thread, you could have folks submit their video to a central uploader who then posts them to the challenge channel, or you could have a central web page for the challenge with links to each contestants channel or page. Th ething is with a build you may have multiple videos. i entered a guitar contest once and submitted 1 video to the main contest page. just ideas on how to do it. If folks re trying to build a channel maybe links to their page os the way to go.