[snip]
I think it a Myth movie would best be done in a manner similar to how we see the game. Basically, take every descriptive scene written in the journal that could be transcribed to film, and use that in place of actual journal text. Only places where visual scenes would not be appropriate - mentions of past history and such - should be spoken, and then in a simple narrative voiceover fashion, as the entire movie is the visualization of a written narrative (the journal).
I would begin it with a slow zoom in over Crow's Bridge. Voiceover speaks, "Wednesday, September 3rd, Crow's Bridge..." and begins the narration. It fades out where appopriate, to be replaced by the actual scene where the Legion enters the village and the peasants plead with them to stay, etc. When that scene is over, it could cut to the Narrator sitting under a tree in Crow's Bridge, writing the last lines in journal entry "16 of us are to say now, perhaps to fight boredom instead of the fallen lords, and watch the bridge here for two days". Then a bit of waiting around to illustrate the boredom, leading up to when the Dark forces arrive and the actual battle begins. We would have to decide for sure who the narrator was, of course, to do this, but I don't think we would have to keep him out of battle. He does fight Myrmidons in Forest Heart, remember.
Where appropriate, scenes would begin with breif excerpts from the journal. In some scenes, such as "Out of the Barrier", when Alric finishes delivering his crazy rant to the Champions, the narrator would interject his comment about how Alric's story contradicts what he knows of history. Then the next scene would shot Alric and the Champions battling out of the barrier, etc.
The movie would perhaps get a lot longer because of all the extra scenes that would have to be thrown in - the Battle for Madrigal, etc - which wouldn't just be mentioned in passing as in the game. But that's not a bad thing - as it stands, the movie would be primarily a long line of pure action sequences with no real consequences, interjected by consequention sequences (the scripted battles and things mentioned in the journal). So the long strings of redundant battles could be shortened to allow the rest of the valuable plot information to fit in.