November2 is classed as a SMuFL font by F27. But of course your old document from F26 is "non-SMuFL". Try to change the font to: Maestro, or if that doesn't work, Finale Maestro, to establish what type of document F27thinks it is.

You'll probably have to do the XML shuffle from F26. 

I suspect the problem is that November2 is a 'hybrid' font with each glyph existing at two codepoint locations, one legacy and one SMuFL. This is counter to the SMuFL spec and can lead to this type of confusion as well as other problems.
Many characters are registered differently in SMuFL than they have been in the legacy fonts.

You have the 'wrong' version of these characters selected in Document Options now that Finale 27 identifies this as a SMuFL document (assuming that November2 is the Default Music Font).

Be aware that these are not SMuFL documents if you created them in v26 using November2 because that template apparently used all the old legacy codepoints rather than the SMuFL ones.
You can expect a lot of problems like this due to the 'hybrid' design of that font.

Robert is easy to contact on another forum and sometimes pops in around here. I’d go to the source on this and see if he has any insight, workaround or a possible fix. It would be nice to see him weigh in on this.  

Ben, Greg and Mike, thank you for replies. You have diagnosed it correctly. The solution from David Cusick at MM was to load the Finale Maestro document options library to the document. This changed everything back to Maestro but corrected the font positioning that you correctly surmised was the problem. From that point I can change the default music font back to November, (might stick to Maestro from now on, though ;)

Thanks again and best wishes,

David