I don't understand why a lot of people in the TS community feel it necessary to have a TS person play the role in the film. In the movie, the role is depicted the same no matter who the underlying actor/actress is. Yes, it would be good for the career of the TS person by giving them another movie under their belt, but if none is available, or they choose not to cast one, then that's fine.
In my opinion, I think it does the community a service by casting high-profile names if only for the appeal that would garner. If people saw this movie and saw that someone they had never heard of (and whom they may not agree with their gender identity) was playing a role they may or may not feel inclined to agree with, they would probably never even consider watching it. However, if they see that a big-name actress is the lead role in a movie with a subject they may not agree with, they may feel a bit less uneasy going to see it.
Now, if there were a high-profile actress who happened to also be TS, then that would make sense that they would be cast for that role. But nobody comes to my mind.
~Sarah