Hi. RodWard. Thanks for your help to answer my issue. I have no quiz inside.
I tested using single cptx file, the "navigate to visited slides" worked well when close and re-enter the course.
But my project is using Aggregator with combining several swf (to overcome bandwidth issue). The "navigate to visited slides" failed when close and re-enter the course. So, i believe this is the Aggregator issue.
I have Backward Movement enable in the Quiz Settings, it cannot help.
Do you have any other suggestion? Thanks for helping me and the community.