The most I could see, and I think I've vocalised this before, is the opening theme song + montage leading into that cutscene, hence it's need to be CG, unlike other games where there's a clear ending point of the opening and when the game begins. I still wouldn't classify the scene as part of the opening though, as I'm very rigid in my belief of the opening being purely the Utada's song.
Now it's just where the Eraqus and Xehanort scene slots in. Will it be like 0.2 where it happens before the theme song or will it happen after Lea and Kairi's scene? Personally I think it will happen before the theme song, showing the clear cut between it as a prologue to the story and setting up some themes for the game and when the proper journey begins.