I have a course where i need to restrict navigation to prevent the learner skipping forward. It is a relatively long course with 5 modules and my concern is that if the learner skips backwards using the menu, they may find it difficult to return to the furthest point in the course. I can't see any way to indicate which menu items are unlocked (the learner could then select the last of these to continue and make further progress). Is it possible to do this? The only other option (which would be ideal really) would be able to lock the menu until the end of the course and then open up the menu at the end to allow the learner to review chosen slides. I appreciate any suggestions about how to achieve this. Many thanks.