thunderclap said:

I figured out After Effects Roto Brush which is pretty damn cool. Unfortunately, in the scene described above R2 has a bluish tint all around so trying to change his color at all affects him entirely. Looks terrible.

It might work if I use the secondary color correction tools in Speedgrade and export the look file and apply it in AE. I'll just grab a freeze frame from the AVI version and try it... (btw, when tracking footage you can have it track frame by frame and make adjustments if needed to keep it tracked. Also making the track point bigger helps, but also slow down tracking time.)

EDIT: Well, fixing R2 in space is pretty much impossible, but maybe it's not needed. If he's just any other droid, does he have to be recolored in every scene? So maybe with preplanning you could only recolor him in areas that work, make sense story wise, and don't cause continuity errors within the film.