Rate it 3/5 which is a "neutral" vote.

Otherwise you can decide to leave it there without a rating, but you'll only be able to just download 9 amvs at a time instead of 10 since you have a video sitting in the voting queue. If by any chance you download other vids of yours and leave them there, this might eventually end up with you HAVING to rate at least one of them to be able to download a video at a time.