Yeah, they swapped Sansa for Alayne. I don't think that scene was handled well at all and it's easily the biggest choice the show has made that I question. I also understand where they are coming from. Book Sansa has basically spent several hundred pages brooding and doing nothing. You can sort of do that in a book, but if you basically have a character doing nothing and being no significant part of the story for hours on end in a television show, it becomes pretty obvious and problematic. That doesn't justify their handling of her character, but Martin's writing of some characters made the TV version really difficult to handle. (Though, for me, reading an endless slog of nothing happening wasn't much easier either)