It worked straight out of the box, creating an attachment link with the file size next to it.
I think I'm missing something as I can't see how to include attachments in the backend when I'm editing articles. However it works well so I can see me creating a new article in the backend then switching to the front end to add the attachements because it is so simple.
Many thanks Jonathan for a nice clean extension.
The ability to add attachments in the back end was added in version 0.9.5 Beta.