I appreciate your inquiry.
Was the exported course a Brightspace Package or an external package?
The Brightspace Package is the default option for exporting courses from Brightspace LMS, it includes all the essential resources you need to transfer your course to another Brightspace site.
Have you looked at Manage Files to see if there are any course files there?
Also, when importing the course did you choose to import the whole course or only some components (such as content, quizzes or discussions).
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