No problem, and thanks for the quick reply. Basically, there are a number of different CPTs which are collected on a user's dashboard. One of those are ‘Project Documentation' where the user uploads a document and a small description. What I was looking to do was to link the post's permalink directly to the post's attachment, rather than to the post itself, or the attachment page. I realise this can be done in wordpress normally but this plugin is so good it's taken over a lot of the site's functionality :).