Resume Saved State Not Working

I have a Storyline 360 created and it's a checklist. There are 5 things end users need to do to complete the whole task, and as they get done with each one, they check the box off to indicate it's been completed. When all 5 boxes are checked, the 'Next' button appears. That part works as it should. HOWEVER, when we close out in the middle (let's say we have 2 or 3 boxes checked) and then return, even though we select "Resume where you left off" all check boxes are now blank. How do I get the checks to remain so they can come back in and simply pick up where they left off? I know the resume works at least some, because if I go to the next slide and then close, when I resume, it takes me to the 2nd slide instead of the first. But still, all checkmarks are gone. Any ideas?