Path to put the clayff-0123 force field files: 

C:\Programmes (x86)\Accelrys\Materials Studio 6.0\share\Resources\Simulation\ClassicalEnergy\FORCEFIELDS\Standard

=AND=

C:\Programmes (x86)\Accelrys\Materials Studio 6.0 x64 Server\share\Resources\Simulation\ClassicalEnergy\FORCEFIELDS\Standard