Ady are you aware of this?
http://www.youtube.com/watch?v=4WCj4Cj2-MI
This might solve many problems of light flickering and slight values that goes up and down during the movie.
I can remember the slight light difference when piet watches vader's helmet goes down (that you fixed) or when vader informs the bounty hunters and the wall behind him flickers.
I dont know if that plugin have a global effect but it would be nice in certain areas are more stable, lightly.
I start to believe that The foundry have many more good aspects and tools from adobe...
-Angel