We agree that the error and condition that you're seeing is undesirable. What is happening is that when a server error happens in such a way that ndOffice doesn't know that the save was successful it tries to save again. But since the data on the server is newer than we thought it was (because it was successfully saved) ndOffice thinks someone else must have edited the document. This is incorrect.
In the next version of ndOffice we will have a safeguard against this. When we have added some information to our server calls that will tell ndOffice that the two docs are the same (the one in your echo and the one on the web) and we won't try to save it again.
Additionally, we're working hard to eliminate the server error that causes the lack of response in the first place.
Two comments, however:
2.1.14 is a pre-release beta copy. You should update to 2.1.18. However this won't change this condition.
Word never autosaves. It does have auto-recover.