This renamed a number of selected JPG files from (for example) DSCN7450.JPG to 7450.JPG
In other words, it stripped the first four characters from the JPG file that the camera created.
I get no error message when I try to run this in DO 12. It just does nothing.
If you're using the default Opus 12 toolbars then any presets you save will appear in the Rename menu automatically, with any favorited ones at the top. You can also make buttons which run a specific preset with a command like this:
Rename PRESET="My Preset Name"
That would do the same as the first command in my post, but let you have access to the same thing in the Rename dialog, with both the button and Rename Preset tied to the same definition, if that is useful to you.