Couple of Possibilites,

1. Try rendering the full movie.

2. or Render 1 light source to the clip and render to a new movie. Render 2nd light to new movie and create yet another new movie then render final light to that.


Good luck

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IBM A51p with 160Gb Boot Disk, 160Gb external Firewire Disk, 2Gb Memory and a super duper sound card, 17\" TFT Monitor etc etc etc
Sony TRV33e : Sony TRV310e : Canon XM2
ULead products mostly including Mediastudio Pro (V8.0), Video Studio 8, Movie Factory 2.0, Premiere Elements

Remember, there is always more to learn than there is to teach.