If I'm going to have a choice of English and Spanish narration on top of the base music. Do I render the AC3 audio for 3 separate files.
1 for the base music
1 for English
and 1 for Spanish?
You should have 2 audio tracks 1 for the english mixed with music, and 1 for the spanish mixed with music. Whatever is the default will normally depend on what the DVD player is set for.