crucial point you have missed.

The new files will have config-sample.php.  Which file should be used?  sample or real.?

You have to be explicit, I mean really explicit.  Just because you know what your are thinking doesnt mean everyone else knows what you are thinking.

@pixelpadre2
config-sample.php is backup file in case config.php would be removed or corrupted.
Using this file as backup has been retaken from wordpress approximatelly 9 years ago.

The reason I ask is because if sample is used, the install process assumes new install and real assumes database update, at least that is the process in zencart.

@pixelpadre2
config-sample.php is not used anywhere in the script.