[enuddleyarbl]

With the pointer to look at the opf, I found some information that the spine in the opf sets the order. So, I dragged the jacket from its 3rd place location in this troublesome book and watched its entry change position in the spine to reflect that.

Saved and quit, then re-opened. Still good.

Quit and ran Modify ePub, reopened and the jacket had been moved back down to its 3rd place location in both the file list and in the spine. EDIT: I guess I shouldn't say it "moved it" -- I've got the "Add/replace metadata jacket" option on, so I guess it's deleting the old one from the 2nd place location and creating a new on in the 3rd place location /EDIT.

It's not the end of the world. But, I just don't understand where Modify ePub is getting its information to move the jacket to that 3rd place in a few books. Usually, it leaves it in the 2nd place location.