How to use gprConvert.py from command line:
0 :: make sure the script directory is in PATH : Computer > Properties > Advanced system settings > Environment Variables
1 :: open a command line prompt : run > cmd
2 :: cd to directory containing GPR files : cd C:\Directory\To\GPR\Files
3 :: invoke script : gprConvert.py
NOTE: The wavelength is an optional parameter indicating the wavelength you used to scan your slides. This is important for locating columns
There is also a gui installer for this program. Just install and use.