I believe that alll you should need to do is the following:
1. Open form in design mode, select File Tab>Publish>Publish to Network Location
2. In the window that appears, copy the location of your shared folder into the Form template path and file name field.
3. Give it a name and select next.
4. In the next window, if users can access the form from the location you've designated, select next.
5. In the next window select publish.
Your form should now be in the folder you designated. Let me know if this helped.