Complicate user setup

I have a site that I need to move over to WordPress and I have one part of it that is causing me a headache.

In the current site – registered users can update their own page (which is viewable externally) and also upload a file for others to download.

What makes it more complicated is the fact that the admin user can upload files – stick them in categories and then enable certain users to see certain categories – which then allow the users to download these files in their private area.

Is there a plugin that might allow this to happen (or are there possibly multiple plugins that might)?

So far I have found the members plugin for roles, document monitor possibly for uploading documents into categories but not allowing permissions to be set by users..

Any help would be great!

Thanks