//// As far as I know, the sixth character will be a downloadable one and will only come out with the DVD release of the movie.
And I strangely, sadly maybe, but honestly don't remember any of the codes to unlock the extra game modes. I can't even tell you if they are actually in the game right now or if it will be part of the downloadable content, cause it was all part of a marketing plan. But if they are in, they were all old games code like Sonic codes or KONAMI codes if I'm not mistaken.