I've a course with 1 question module and 5 SCORMS - I've set the certificate to only issue is all parts are above 80% - this works well.
The BUT is if I modify one of the SCORMS (by uploading a new SCORM eg I fix a spelling mistake) then even though a person shows in the grade book as completing all 6 parts the certificate says "You must first meet all course activity grade requirements before receiving your certificate"
If the person goes back and redoes the newly upgraded SCORM they get their certificate - seems as though the grade book and the certificate look at different things.