Sorption: settings forcefiled preferences files

Hi,

I have to change the COMPASS and Dreiding

forcefields  with new parameters. (Material Studio 4.0). On the tutorial is written that it can load a file with new parameters "settings forcefiled preferences files", but do not specify how to do this. Where should I upload this "new file"? How I can evocate this in Sorption modules?.

Thank you at all.

Marcel