You can either enter the path for the files directly or use your operating system's file selector. The paths that will be saved are the paths displayed in the text fields.
All comments are preserved when reading and writing parameter files with FLASH Interface.
The flash.par file you would like to read from.
The flash.par file you would like to write to. Usually the same as the read file.
The setup file to get your default variable configurations. Usually called setup_params in the object directory.