Course Tracking

Hi everyone, is there a way of tracking a course completion when users reach a specific slide number?  I have a course which doesn't have a test, but has scenarios, so they may not visit every slide.  Under the tracking options, even though the max number of slides is 72, they may only visit 65 of these slides.  My concern is that if I set this at 65 and they have already visited 65 of the slides before they reach the end of the course, it will show as being completed.  Has anyone come across this before and is there a solution?