This shows you where to find the PGW library for your active configuration. You can make a backup from this.
Changing between configuration libraries are made with the "config-lib" tool under /opt/CiscoMGC/local
Of cause you can use the files from 'prov-exp' command but e.g. if you have lots of dialplans need to know all relations and dependencies and it takes a much longer time.
Best examle is a hardware upgrade: all you have to do is installing the new hardware and PGW software like described in PGW2200 installation guide and then you copy your backup directory from the CONFIG_LIB folder to the new PGW.
With the ./config-lib tool you can copy this library to your active one.