"You have an unreleased version."
In both cases, it turns out, I have the most recent update as published on the Garritan support site as well as the Plogue website.
Also, when I click the 'open in text editor' to modify some sfz's, I get 'this is not a text file,' even when I can confirm the file is saved from text editor as pure ASCII (no utf or other character encoding). This, of course, may be a Mac thing.
And neither of these are stopping me, just slowing me down.
Clicking update Aria Player and Engine produces error
Moderators: Peter Thomsen, miker