Site Cleanup/Unused files

I've seen a couple of old threads on this, but wondered if anyone might have new or better suggestions.

I purchased a template online that came with a number of different "versions" and images files. The first thing I did was select the version I wanted to use and copied it to a new file with a new name. As I've been working with the file, I've done a lot of custom work and have changed the css a lot, as well as created new images in Photoshop.

At this point there are many, many files that are not being used in my custom .html file.

I know in InDesign you can "package" the project, and I wonder if there is something similar in DW2017 (or an extension). I've tried the orphaned files report in the Site menu, but it actually gives me false results; I know some of the files mentioned in it are actually called in the html or in popups.

Thanks everyone.