As far as timing out with

As far as timing out with facial motions and everything, I would record their audio first, put it on an mp3 player, and play it during the shoot so they can walk and react to the voiceover easily.  Shoot a lot of different camera angles and focus and just do take after take until you have more than enough footage to work with.  The worst thing you can do is not shoot enough and leave the editor with holes. 

Jon

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