There is a v5.5 but this is not an official release yet.
V5.5 is only for the people who upgraded and have a security problem with the new 5 digit security.
Before there were 4 digit security, now there is 5 digits. Some companies or people has problems with starting up the software. In this case there is a v5.5.
I believe there have nothing more changed than that.
That is what a official pangolin dealer told me.
If there is a new release with some nice upgrades and something new I think Pangolin release it soon.