I have no idea. It doesn't look like it should 
need the backlighting. Are there other cels in 
the sequence that are backlit? She looks like 
she's on a stage - a flashing light behind her 
maybe that would only effect some of the sequence?
If other cels in the sequence *do* need to be 
backlit, although yours doesn't, it's always 
possible yours was painted to be backlit by 
mistake?  Or maybe the sequence might have needed 
to be backlit, but they changed their minds? 
(*shrug*)

And my secret for posting multiple images is to 
not post multiple images. ^_~   I just create a 
composite image of all the individual images that 
I want to display. Separate them with black (to 
blend in with Yann's page) and you can't tell 
sometimes that they're actually one image. ^_^

Many Sharp Smiles,
--Drac