Allowing other users on my iMac access to my Aperture library

I popped in to chat to a local Apple bod at PC World and took some advice on how to allow users on my to access my Aperture library.

He stated I should move the library to my 'public' folder from where others can access it. That didn't work! I then looked through advice on here and one person had stated that moving the library into folder that was located outside of 'Users" might do the job. To also ensure permissions for the library and folder were set to Read and Write for all. I've done that and still I get the same message as I try to set my partner and daughter up to access my Aperture library.

The message reads:

Unable to write to library "Aperture Library"

and to basically check permissions.

Nothing I do seems to evade this problem.

My Aperture Library does reference a lot of photos that are in my Pictures folder under my user account. Could that be it?

Any help would be appreciated.