More Buttons for Customization

looks like you could go into the plugin file
genesis-author-pro/classes/class.Genesis_Author_Pro_Book_Meta.php

and twek this:

/**
	 * Builds the button field output.
	 * Calls the object meta_rows() method to build the text field output.
	 *
	 * @access private
	 * @param array $field
	 * @return sring
	 */
	private function _get_button_field( $field ){

		$rows = array(
			array(
				'name'        => sprintf( '%s_uri', $field['name'] ),
				'label'       => sprintf( __( '%s URI', 'genesis-author-pro' ), $field['label'] ),
				'type'        => 'text',
			),
			array(
				'name'        => sprintf( '%s_text', $field['name'] ),
				'label'       => sprintf( __( '%s Text', 'genesis-author-pro' ), $field['label'] ),
				'type'        => 'text',
			),
		);

		return sprintf( '<table class="form-table"><tbody>%s</tbody></table>', $this->meta_rows( $rows, false ) );

	}