I realize this is an old post, but I wanted to say "me too, please" for this feature request. What I really want is an option (e.g., a checkbox in the preferences/settings section dealing with renaming resolution) that will put an underscore between the resolution and the rest of the filename. Or maybe the preferences setting could allow the user to pick the separator character (some may prefer - or a space to _). e.g., if I rename based on date and time and end up with two files called "20230420_151213.cr3" then I'd like the resolution to be "20230420_151213_01.cr3" and "20230420_151213_02.cr3" rather than "20230420_15121301.cr3" and "20230420_15121302.cr3".
And, based on my example, I guess I also would like the first file to be altered as well, but ONLY when duplicates exist. I think currently the first filename is unchanged, and the second filename is tagged 01 … unless the "always append digits" option is selected, but then EVERY file ends with 01 even if there are no duplicated names (and in this case, I could just add the trailing _ to the renaming structure).
