You need to make a shortcut to the exe file, then right click it, go into properties, and in the target window, at the end add " -developerkeys" without the quotes. Make sure there's a space between what you add, or it won't take. Use Page Up and Page Down to switch between characters. You can also add " -developer" to use cheats. Keep in mind that the game will crash at cutscenes with any other characters.Also, disregard my earlier comment (if it popped up), I just woke up at that point and misread your comment.