I must admit, I am a little late with these “news”. But in case you did not realize it yet: NagVis 1.6 has been released as new stable release of NagVis. It replaces the version 1.5.10.
NagVis 1.6 comes with a lot of new features and improvements. If you are using older versions of NagVis you should definitely take a look at the official announcement and the change logs of the different 1.6 pre releases which are linked from the download page on NagVis.org.