its a little known inside tip we got from a cm, as libby was so mad that she didn't get her photo with belle and snowwhite, despite having queued for 40 mins, a cast member called sean told us to go inside the castle and turn right and down the slope, you see a blue door and wait there so we did, then when its changeover the princessess come out of that door and come back from the stage area to go inside, if this makes sense, i think it helped that libby was dressed in her princess dress and was holding her snowwhite dolly, they just stopped despite a cm telling them not to.