Show Locations on the maps by exlcuding certain categories.

gistfile1.txt

add_filter('wpgmp_location_criteria', 'wpgmp_location_criteria',1,2 );

function wpgmp_location_criteria($location_criteria,$map) {

  //This will apply for map id 1.
	if( $map->map_id == 1) {
		$location_criteria['show_all_locations'] = true;
		$location_criteria['category__not_in'] = array(1,2); // You can use category name as well. 
  	}
	return $location_criteria;

}