With the new version of Checkpoint Smartcenter R80, the way to obtain the rules has changed.
To export the configuration from a Checkpoint R80 we are gonna need to download a tool from the Checkpoint's Github. We want to be sure we download latest version of the tool since the one it comes installed in your SmartCenter usually is old and may contain bugs.
So first open your preferred web browser and go to:
The output from that command will let you know what Packages are available to export
Last command we have to run is the following where PACKAGE_NAME is the name you have chosen from the previous command and in case you are in a MULTI-DOMAIN environment specify the DOMAIN_NAME too (-d is OPTIONAL):