Ok, so that shows that emacs-el.lst.gz was corrupted. I deleted it,
then reran setup. I clicked "Exp", then "View", then scrolled down to
the three "emacs*" lines and set them all to "Reinstall" (the "Current"
column says "23.0.92-2") and clicked "Next". It chugged for a bit, last
displaying "Uninstalling emacs-el", then reported "setup.exe has
encountered ...". After dismissing the dialog, I looked at /etc/setup
again, and the corrupted "emacs-el.lst.gz" was there again. I also
checked to see whether any other "*.lst.gz" files were corrupted, and
there were none.