The Course Rules state that a CD must be present at a course when a CDC of FI needs assessment.
9.1.5 The CD may supervise the course remotely.  In case CDC or instructor assessment is needed, the CD needs to be present.

When you want to add a CDC to a course, you will need to do following steps. 

Step 1:
Change the setting of the CD from "unknown" to "present at course"
Click on the pencil next to unknown, a dropdown menu will appear:

Adjust "unknown" to "present at the course


Step 2:
Add the CDC to the faculty: Course Director Candidate is now visible as qualification.