Admittedly not a very big deal, but there is something in my Opus 11 configuration such that when I restore a backed up configuration Replace existing configuration completely is pre-selected. Does anybody know what to tweak in Opus 12 to cause this default?
This is not really an Opus 12 question. It's a configuration question. I'm reasonably sure I remember Steje posting some trick to achieve this years ago, but I don't remember the trick. It may have involved editing some configuration file, but I don't know.
It's probably in /dopuslocaldata\State Data\backupconfig.osd
Copy the number x from the machine that does what you want.
I'm not sure if restoring the config will overwrite that file. It may do, if the config backup includes state data. If it does, you might want to re-make the config backup (or edit it by hand; they are just zip files really, if you rename them).
Remember that, as with all version changes, config from Opus 12 won't load into Opus 11 without at least some small issues. (11 configs fully load into 12, of course.) So don't replace your Opus 11 config backup with one made in Opus 12 unless you know you won't want to load it into 11.