Bluray authors can split a movie into as many m2ts files as they like: the definition of which particular m2ts files constitute the movie and in which order is held in the playlist (mpls).
There may be many playlists on the disc, some of which are fakes to make playback more difficult when copying.
AnyDVD HD often has to be updated to find the right playlist and ignore the fakes on new releases. Check in the Slysoft forum to see which version is correctly handling your title, or whether it is still being worked on.
Open source Bluray players are starting to become a reality. Otherwise ClownBD can create a movie-only version, consolidating any fragmented m2ts files into a single m2ts file.