I've figured out how to get phpDocumentor to work with Windows 7 and XAMPP using the Composer install method.
I'm sure this can be documented better but I'm short on time.
Hope this helps someone else.
-- Christopher Mullins
Thank you for sharing this. This can be added to the installation document as a XAMPP footnote or in the FAQ. If nobody beats me to it (which is of course appreciated) I can add it to the documentation.