caribmedia said:

We are looking for a way to offer multiple users their own 'post' where they can upload files, and create links to those files.

Define your users as Authors. They will be able to submit and edit their own posts, but not edit any others.

We do not want other users to see those posts, nor do we want them to see another users posts or uploads.

Role Scoper will prevent other users' posts from being listed in the Edit Posts list.

So the restrictions are quite heavy for the users. The posts can also be pre-made for them, we already know who the users are.

If you pre-publish the pages and save them with the corresponding user as Post Author, you could then prevent addition post creation by using Role Manager to remove the publish_posts capability from the Author role.

Preferably every user gets their own url for files as well, so when I have a post named /users/bert I would get links to /users/bert/files/berts_file.pdf

That's not a job for Role Scoper. Not sure if a free solution exists; search the WP plugins directory for "user permalink". Worst case, you can always manually define the permalink for each post/page.

Is this a viable scenario and how would it be implemented? we are willing to set a password on each post.

To limit read access you could set a password or mark the post as private. Marking it as private would enable the user to specify which other registered users can view it.

Instead of posts we can use pages if that is easier.

Default page permalinks would be closer to your desired result. To use pages, you would need to modify the users' role definition to include the edit_published_pages capability.