I know it sounds like I'm being a pain, but I'd rather not. I've tried uncommenting everything but the part that applies Colourlike, and it makes no difference.
a=Avisource()
b=Avisource()
ColourLikeFBF(b,a)
The relevant part is written like that. If there were a syntax error, I would receive an error message upon opening my script. Is the length of the movie a possible factor?