In Linux and Windows, this file is stored in the same directory as the Key Generator. The Generator will download and use the most recent copy of the file. (You can over-ride the detection setting, using the 'CIC/NBT' radio buttons).
This is (hopefully) a more user-friendly CIC/NBT FSC Key Generator for Windows, Linux and OSX based off of the work of the original FSC Key Generator and Intel123's certificate Patcher.