Cannot Set Default Font As Described in Instructions
Operating system version
OS X 10.9.4
Description of the issue
I'm working on a Mac with a file that I ported over from the Windows environment. Its default font is set to Arial 16. I prefer it to be set to Helvetica 12. I went to File > Preferences > Font and chose Helvetica, but the default font in Layout mode is still Arial (altho at least it's Arial 12; no idea why; the font-size drop-down menu still says 16 when it's in its rest state).
So I consulted the on-line help, which provided me with the screenshot uploaded below, promising me that I could set the default font if I worked with the Appearance inspector with nothing selected. In trying to do so, however, I ended up with the drop-down font menu (still reading Arial) grayed out and thus inaccessible to me. I have a screenshot of it that I'd be happy to share, but evidently I can only upload 1 image to accompany this message.
Steps to reproduce the problem
It's very consistent. It behaves the same way as described above every time.
That, following the instructions from the Help feature, I would indeed be able to set the default font to Helvetica 12.
It stays at Arial 16.
Exact text of any error message(s) that appear
Insert new fields as Arial 12 and change them to Helvetica manually. Not my favorite way to spend my time.