We have sent you the file after fixing it. Let us know if you are still facing any issues.
Adobe tech support "uncorrupted" the indd file I sent them (a file from
Adobe's Classroom in a Book series) then they saved it as an idml file.
Problem solved -- at least for that file. Thank you. It's still not clear
to me, however, whether this was an isolated incident or something more
systemic. I guess I'll find out the next time I try to save an indd file in
the idml format.