Q3.1.6: How can I have the window title area display the full path?

I’d like to have the window title area display the full directory/name of the current buffer file and not just the name.

Add the following line to your init.el:

(setq frame-title-format "%S: %f")

A more sophisticated title might be:

(setq frame-title-format
      '("%S: " (buffer-file-name "%f"
                                 (dired-directory dired-directory "%b"))))

That is, use the file name, or the dired-directory, or the buffer name.