Please download the attached zip file and unpack it in one of the following directories, depending on your OS. If the path doesn't exist, you need to create missing directories.
Windows: C:/Users/<your user name>/AppData/Local/Flirc/keyboards
OS X: /Users/<your user name>/Library/Preferences/Flirc/keyboards
Linux: /home/<your user name>/.config/Flirc/keyboards
These are standard paths. If you've customised your OS by changing your home directory location, they may be different.
After unpacking the file, restart the Flirc GUI. You should see a Numeric keypad in the Controllers menu.
numpad.zip