Just to quickly add to that I am finding it hard to make the alpha channel transparent when importing the lightning strike as a movie. As I said in the previous post I seem to be able to do this with one TIFF file but not a sequence. How do I check that the .mov file definitely has an alpha channel? I think I exported correctly from AE but my mistake could be there and not in C4D. The Image sequence in TIFF’s are definitely alpha channelled as I have checked those.
Ouch, globals, serious render times for me as the final render needs to be HD video out. I’ll try lights first and then cheat it with timed lighting in unison with the vid and then if all else fails a global illum.