Hi -- I've just installed the authoring tool via Vagrant, and I'm encountering the same issue: i.e. the back button isn't working in either the preview, or when I export the course and 'build' it using Grunt.

The adapt framework version seems to be 2.0.2.

This issue seems to have also been flagged here: https://community.adaptlearning.org/mod/forum/discuss.php?d=1184