The emacs functions mentioned in the docs don't seem to exist in my org version 7.9.3f.
Any idea how I can get org-mode to export to markdown for me without pulling my hair out?
You should customize
org-export-backends and enable the markdown backend.
I just ran into this package:
If you want specifically Github-Flavored Markdown, that should help.
It can be done using pandoc:
pandoc -s progress.org -o progress.md
Have you tried
(eval-after-load "org" '(require 'ox-md nil t))
as discussed in this answer? Once loaded you should see the export option in the normal org export list.