Hello Andres,
Best Practices say to 'sometimes' take a ZD configuration backup, and 'always' take one before
an upgrade. *And you need to add some digits to your filenames, to identify what version and date
on your backup files!
If you have previous backups, you need to be running the version they were saved on, but will
have to look at the Admin screens to determine any changes... there isn't a Text output of configs
that can be compared offline I'm afraid.