"I can't find any referance to 5.3 on the Cloanto Web Site yet???"
Sorry - my bad! I assumed Cloanto would've posted this on the website - Existing users of Amiga Forever 5.x have an update tool called "Software Manager" - if you run that and click on "Check Now" it'll show 5.3 available for download.
I guess they've spent more time tinkering with Amiga Forever than keeping the website up-to-date
:-)