When you're ready to reveal an existing Course draft, head to the /admin page and:
SELECT "AUTHOR"
SELECT "Courses"
FIND the Course you want to change
Publish a Course
MOUSE-OVER its box to reveal pencil and trash icons
SELECT the pencil icon
SELECT "Re-Enable" (top right, if it's a retired Course)
SELECT “Publish” (top-right)
CONFIRM to make it happen