You should have just complimented her on her dress and that could have opened a door to communicating with her. Everyone likes being complimented and having something on out of the ordinary usually means that they dont mind the attention that it will inevitably get. Good luck!!
I know. I thought about it. I was going to catch her as she got up to leave, but she was out the door before I realized it!
I hope I see her again! :)