So I can’t reproduce exactly what we are seeing on the demo site, but here is a screencast Previous button goes to wrong section (demo site) - YouTube … What I am seeing on the demo site, is it doesn’t go back to the previous section but to the start of another section possibly?
This video shows what are seeing on our site with all of our different lessons.
I believe we also see this same behavior when using as an LTI integration, but I will have to work with @Anderson to try and duplicate that on the demo site