Also (I saw the film twice at the cinema so no guilt tripping me regarding the copy I saw to asses this), but that scene where the alien disappears down the ladder toward the end? If they can, they desperately need to sort that out before home release. The CGI effects seem half done in this film. Those tubes on the alien's back didn't just fold up, they literally 'clipped' through the floor.
I couldn't quite tell in the cinema, I thought it was going to be an unfinished effect left in the trailer.