Sorry it took awhile for someone to answer. I just went thru this for someone on LinkedIn. "cmi.score.scaled" is the main one you'd want to make sure is getting set.
I have a Gist up in a similar fashion with an example of the prereq and ability to rollup the score properly. https://gist.github.com/cybercussion/11192402
Also a sample CAM with QUnit Test. https://dl.dropboxusercontent.com/u/47351904/samplecourse.zip
Edit: Adding a Test to match the use case: https://dl.dropboxusercontent.com/u/47351904/samplemultisco-intro-test.zip
First QUnit SCO test will only set cmi.completion_status, and cmi.success_status (completed/passed). Second Qunit SCO will run 10 objectives/interactions and set a score of 0.75 (75%). imsmanifest.xml updated to match the needs of a pre-test SCO followed by a quiz/test.
Thanks, Mark