Chris
All software requires updating. Every few years we require a paid
upgrade and in between those periods we create new builds almost weekly
that deal with things that come up.
The v4.0 platform consists of all versions and builds from 4.0 to 4.3
and ran the gamut of systems from 10.4.11 up until 10.8.5
In 2013 we introduced v4.5pro and offered early adopters a lower upgrade
price so we could transition without issues given that AVID often does
throw curve balls at all of us. And users who needed to work with the
latest operating systems were required to upgrade.
Now 4.3 has long been replaced by 4.5 so if you need to work with modern
systems and you own a 4.0 license(4.0-4.3), then you will need to
upgrade and this has been noted on our front page for some time. Some
of the major feature changes are noted here:
http://store.soundminer.com/blog/v45pro-info/
I hope this helps
steve