Hi,
Are the users not able to open the New-item-form (they don’t see the new-button) or do they get an error message when trying to save the item?
Or is the problem that they don’t see the DFFS config, but only the normal SharePoint form?
If it is the last scenario, you must ensure the users have READ access to the SPJS document library where the DFFS-script files are loaded from.
Alexander