Dreamweaver CC 2017 won't properly compile sass files into output directory

Now that Dreamweaver has support for SASS, I'm trying to use it to manage files for a web application, but a project structure that works perfectly in Scout is seemingly invalid inside of Dreamweaver. I want to believe it's user error, but I can't figure it out.

The project was originally built with a flat css file, but I'm trying to update things a bit.

Ultimately, I want the compiled CSS files to go into resources/META-INF/styles, but I want to store the SASS files in resources/sass.

I've got my source and output folders defined as shown above (I stripped out a lengthy site root for readability).

At this point, when I attempt to compile a sass file, I get the following error:

Everything looks right according to the settings I've defined:

If I dump the contents of my sass directory into the styles directory and then set my source and output folders to be the site's root, it compiles just fine, but I don't want to clutter the styles folder with sass files unnecessarily.

Also: If I setup this project in Scout using my desired folder structure, it compiles as expected, so I have a workaround, but I'd really like to eliminate the extra step of running Scout every time I modify the CSS, because Dreamweaver should be able to handle this (if I can figure out how to set it up correctly).