The answer is "YES!!!" Many of us are having similar problems. My wife uploaded her first book to PubIt! last week and received the "Technical Difficulties" message. We thought it wouldn't go. Plus the book's status in her book list was "processing" which is a kind of limbo state during which the author is not allowed to delete it or make any changes.
Fortunately, for us, her book appeared for sale about 11-12 hours later as if everything was okay. And it has been successfully selling since then.
So, even when an error message appears, you can't be certain what it really means. It may mean nothing.
Unfortunately for us self-publishers, the ebook industry is still fairly "new" and many kinks have yet to be worked out of the system. Nowhere is that more evident than the multitude of problems and poor support at B&N and its PubIt! self-publishing arm.
What can we do? First, I strongly recommend that you contact both PubIt! and B&N and let them know in writing what happened. They need to hear about your trouble or they will not appreciate the magnitude of the problems.
Second, we have to have patience. If you want to self-publish your ebook for the Nook platform, then you have two choices and neither are trouble-free:
 Submit your ebook directly to B&N via PubIt! or  use a third party distributor who can do the same for you, like Smashwords.
Personally, I prefer the former because it gives me total control of my ebook's quality since PubIt! accepts ready-to-publish ePub files. And it gives me the opportunity to use DRM, if I choose. Smashwords does neither—they accept only Word docs which they process through their "Meatgrinder" converter and they offer no DRM. I avoid all such automated conversion systems because they generate a number of problems for which there is no remedy. And they promote poor layout quality for reflowable text.
Until there are better systems in place, we're stuck with these problems. So think of the frustration as simply the "cost of doing business" on the Nook platform.
Kind regards, David
I've been trying for 2 days to make some minor changes and I consistently receive the "technical difficulties" error. I even deleted a title and attempted to re-add it, same error. This is beyond frustrating.
Have been having the same problem since last Sat. "Tech difficulties," etc. etc. Finally got someone at 866-597-9863 who said the pubit dept. was very small and he couldn't help as it was a technical problem for which he was not trained to handle. So I wait to see if my changes have been accepted. Frustrating indeed.
Hmmm...you would think they'd have web site staff that could respond to this sort of problem within a day or two?
I've received the "We are experincing technical difficulties..." error everytime I have attempted to make edits to my book's file or description since Friday evening. Today is Tues 12/18 - so that error is still happening 4 days later! That is no way to run a business.
I hope they can resolve this before their announced 12/21 end-of-year cutoff for submissions/changes.