You should split your database so you have a backend for the tables and a frontend for the forms, query, modules and macros. Save both the backend and frontend to a network location where all 12 users have access to. After the database is split, place a copy of the frontend on the 12 desktops. This gives all 12 users a copy of the frontend that is linked to the 1 backend stored on the server. To split your database:
On the Tools menu, point to Database Utilities, and then click Database Splitter.
Follow the instructions in the Database Splitter Wizard dialog boxes.
Before splitting the DB you may also want to set the startup properties (Tools - Startup) to open your main form and hide the database window.
Hope this helps.