Well considering Alex's dress got caught in her heel for half the dance, which effected her committing to her moves, I think she did well.
As things stand, I feel it's Robbie's time to go (long overdue imo), and if no change then Alex should leave next week. Unless, she does an outstanding performance, which I suspect tonight would have been if it weren't for her dress getting caught.
I think Holly might be OK, but am concerned for Alex.