Revealing mistake: During the fight scene on the riverbank when the white haired man lands on the pavement, the "concrete" pavement moves.
Revealing mistake: When Corso is being pushed through the floorboards (into his proper niche) we can see for a good second or two that it is certainly not Johnny Depp. (The stunt-double is Dominique Fouassier). (01:59:25)
Answer: She was not given a name, neither in the film nor credits. She is simply known as "The Girl". As to precisely who she is, it is deliberately left ambiguous. But the last engraving found by Corso does seem to indicate that she is the Whore of Babylon mentioned in the Book of Revelation.
Twotall