I have Pro 11.19 64 bit and am planning to upgrade to v12. Will that preserve my current settings and defaults from v11 or will I have to start from scratch and do much relearning?
Also on one of my two PCs, I will be upgrading to win10. Will I be able to install v12 on that machine and bring over my current defaults from my Opus v11.19/win7 machine to save time? If so, which files do I have to copy? Thank you.
The only thing Opus 12 will reset is font sizes, to the best of my memory. That's done because of the new high DPI support.
You'll have the default toolbars when you first install a new version, but your old ones are kept and can be switched back to. There's a FAQ near the top of the list with details on that.
Installing 12 over the top of 11 will update the existing configuration in-place. Note that 11 may not understand all config details from 12, so if you want the option if going back, you should make a configuration backup first. Making a configuration backup is a good idea occasionally anyway, of course.
Configuration backups can also be used if you want to move Opus to a new machine. You can do them via Settings > Backup & Restore in the main menus.