Post Affiliate Pro provides you the ability to provide country-specific commissions within each campaign.
How to set such commissions up?
1. In the merchant panel navigate to Configuration > Plugins and activate the "GeoIp Core" plugin and also the "Post Affiliate Pro GeoIp" feature at Configuration > Features
2. Restart the application by pressing CTRL+F5
3. In the merchant panel navigate to Campaigns > Campaigns manager > click edit (pencil icon) next to any campaign > Commission settings and there will be a button called 'Add country specific commission' next to each commission type.
NOTE: The Google API key is only required to display the maps in reports correctly. It won't affect the country-specific commission tracking.