Interestingly enough, I have received private 
responses indicating agreement that if there is 
any responsibility for the tragedy, it's not 
mine.  There have been no suggestions on what 
might be an appropriate or expected thing for me 
to do in response, which was my reason for 
posting in the first place.   

I have, both above and in a private email, 
offered to work something out about this since I 
feel really awful about the damage to the cel. I 
have had no response thus far.

Just wanted to let you all know that, since I 
value your company and opinions, and I don't want 
people thinking I'm some sort of scam artist. 
(^-^) 

On the other hand, I surely have learned several 
things from the experience.  I adore my cels, 
including the ones I have sold; I know how 
fragile they are, and have taken what I thought 
was the best care of them.  I've learned  1) that 
the gremlins can manage to create havoc in spite 
of everything; 2) I will not offer a cel for sale 
again without insurance and a big honking 
disclaimer in the text (not that anyone really 
reads them, myself included); and 3) steel cases 
might be a good idea. ;-)  Oh yes, and 4) there 
is no agreement on best practices.