I especially like how you tell what pieces of the 
image are on what layers. ^_^  That's the first 
thing I like to look at when I get a new cel that 
has more than one layer!

Since it seems like your scanner was cropping 
your cel scans to image area (or I'm wrong?), one 
idea you might try if you don't want it to do 
that is to lay a thin strip of black paper along 
the top of each cel as you scan it. The scanner 
will read the black as part of the image, and 
scan the whole thing. Then you can trim off the 
black part in an image editor. ^_^

Many Sharp Smiles,
--Drac