Just wondering. I did install v60.0 over the top of v52.9.1 and everything seems fine ('cept FireTray addon doesn't work anymore, bummer). But I'm thinking that as v60.0 is a major revision if it's better to start right from scratch again. (Want to avoid that if I can as lots of tweaks to replicate again if I have to start from scratch.)
That's the standard way to do an upgrade as per the support page: https://portableapps.com/support/portable_app#upgrading
Unlike ZIP sorta-portable apps, the PA.c Installer handles all the upgrading, preserving of settings, etc for you.
Sometimes, the impossible can become possible, if you're awesome!