To the best of my knowledge I have implemented the page links correctly.
I have named the pages (are there any restrictions on naming?)

Yes, when I double click the NavBar, the URL column does show the correct page name.

On the live site, when I hover over the relevant drop down menu item, the info bar at the bottom of the screen shows "http://localhost:8000/virt200df1b4/focus_area_quality_compliance (I renamed to remove spaces and an "&" in the page name but this did not work either)

I wonder if there could be some issue with the setting up of the local server?

Having said all that, in playing around with the naming of one of the pages and the link to it off the drop down menu (as noted above), strangely, the menu navigation now seems to be working for all of the drop down entries I had actioned! It is a bit weird.... but at least now that seems to have fixed itself

For the jump to navigation on the page, I have done 'Link to Heading' and selected the heading from the name in the drop down list. Seems straightforward...
And yes, the pages are long enough that the browser will need to jump down to an area out of view.

Interestingly, when I hover over the button in the browser preview, the URL that is displayed at the bottom of the screen ends with "....page name#" but there is no final locator for the heading position. Is this correct?