Hi Amanda,

the abilty to start a new attempt will only be available if the existing SCORM attempt has a completion status of "complete" or "passed" - if the completion status is "incomplete" or "failed" or another status it will enter the existing attempt. This is just how SCORM works.

More information on this here:
http://docs.moodle.org/22/en/SCORM_FAQ#Handling_of_Multiple_Attempts

I'd like to add a new setting to the force new attempt drop list which I descibe here:
http://tracker.moodle.org/browse/MDL-32585
Feel free to vote on that issue or if you are interested in funding the time to develop the improvement drop me an e-mail.