Hi Jeff,
I had addressed an issue with Starfield here
http://forums.creativecow.net/thread/7/854840#854842
Basically Starfield in AE should be applied directly to your footage or on a new Adjustment layer with
something behind it. Because it won't render without a background.
For example if the only layer behind/below starfield is keyed footage, then your only going to see it render where the matte is visible.
When using Starfield I first make a solid, with the background color I need, on the bottom layer. Then apply Starfield on an adjustment layer on top of everything else. The rest of your layers can go between or above those.
