Coursepress Pro uploaded files broken links

Files uploaded inside of CoursePress can not be retrieved and downloaded by Instructors. The links to the files download corrupt files with no content.

I've verified that the documents are being uploaded to the local web server and reside in the proper folder structure - and are fully in-tact:
site > wp-contnet > uploads > sites > 3 > 2016 > 03 > the_document

A working example of an upladed file on my server is:
(unfortunately for some reason, all the uploaded files return 404 errors, despite my verifying their existence through my FTP client looking into the folder structure)

The URL in the Coursepress Pro Student workbook that links to this file is:

I"m trying to find a workaround or a direct-access URL to modify the Coursepress plugin so that instructors can easily download student files for grading.