Composite Color Matcher

Hey,

I'm trying to match a green-screened foreground element against footage of a busy road at night. Composite Color Matcher works great, especially as the background lighting changes with every frame. I was wondering though whether there's a way to get Commotion to automatically sample the target layer with each frame, as the clip is a few thousand frames long and keyframing each frame manually is time-consuming and tedious. Or if anybody can suggest an alternative in AE or Shake?

Thanks,

James