I wrote to pubit support and apparently they didn't understand the issue. They preferred to blame it on my denseness rather some difficulty with their system. I felt very much as if self-publishers are working on their own at BN.
And I also got a little canned lecture on reviews, as if I'm somehow wrong for objecting to a person writing a multiple part short story about cats in the review section of Dream Horse.
So here's my advice. Until Barnes & Noble starts asking for a Table of Contents, don't bother.
There is something about the code in Word their system can't handle. If it works with Scrivener or something else, and you don't experience any issues--great. For the rest of us--ungreat.
Amazon has suggested it's wise to include a TOC so all your documents headed for Kindle should include a TOC from now on.