building clay structures

Users, I am trying to create a Montmorillonite clay data file to read
into LAMMPS using the modified clayff forcefield. I initially used
Material Studios to build and export the .car and .mdf files, but the
current version of msi2lmp does not properly convert periodic
structures (it connects boundary atoms on opposite sides, causing it
to 'explode'). Since msi2lmp is no longer supported (as of 2005?), and my C++
skills are still limited, are there any suggestions as to other
software I can use, or would anyone have a structure I can download?
I have used the P1 valued reported by Viani.

You can talk to Jeff Greathouse at Sandia (CCd),
His group builds clay systems and I think they
are maintaining msi2lmp is some reasonable manner.