Both this project and KompoZer are pretty much dead development wise.

NVU 1.0, released in June 2005, is the last official release that you will find at most download sites, however, it isn't the newest or best version of the Nvu software. An unofficial bugfix/update called "KompoZer" is available here. KompoZer fixes some of the major bugs and annoyances found in Nvu 1.0. If you are using NVU 1.0 and it works for you, stick with it. But if you run into problems, give KompoZer a try and see if it helps.

http://www.net2.com/nvu/download.html

But KompoZer has it's own worse problems. I have also commented on it.

Does not support xml files. Makes alterations to raw HTML, messing up layout on untouched elements in page.I cold not find a preference to tell NVU to stop messing with the code.