After assigning Manager access and despite resetting all my access to Full Access, I originally had only limited access to breakback (limited to the sections in the course that the manager had access to, I cleared write access to geos and regions (was Total Company then I deleted this to try to rectify the previous problem)
After i did this, I saw nothing in PY Sales Module
Even though you have full access, you still have to give yourself read/write access to the list(s) having Selective Access. If you don't set your own Selective Access, then the modules containing Selective Access Lists will appear empty.
To set selective access, navigate to Settings, Users, and then find yourself and set (write) access accordingly.