I did it! I completed the Advanced Lucid Task (with the portal.) It was towards the end of a lenghty lucid dream (you can read the rest in my DJ, if you really want to):

I decided to make a portal out of the mirror, so I picked up this kid and let him put a drop of water on it. (Not sure why.) I tried to get the kid to go through, but his head would just bang against the glass. So I flew through it, and suddenly I was through the mirror and in outer space! Unfortunately the dream ended.