I am publishing from CP 2017 and have set the TOC to "only visit viewed slides" which in every other instance (published in another LMS) means that you can not jump to slides that you haven´t viewed yet. But it seems that in Prime this is not the case.
Also you can jump to any part in the module using the playbar that is switched off by default in CP 2017. We don´t want that!
This is a problem with Prime. I have talked extensively with support and there is no way to eliminate the play bar. I think this is a really bad design. I have clients who insist in restricting navigation and with the play bar that is impossible. You can change the completion criteria to add in "Slide View" 100%. Then they have to view all the slides to achieve completion status.
It is not a great fix, but has kept our clients happy. A better idea would be to be able to get rid of the play bar all together.