Hello, thanks for your purchase.
Please note that in Porto description we do not mentioned anything about drag n drop site building editor.
Porto also has a WordPress version which has Site Builder.
Porto WordPress: http://themeforest.net/item/porto-responsive-wordpress-woocommerce-theme/9207399
If you consider to purchase the WordPress version we can make a refund from the HTML version.
All support related to payment and refund is run through Envato’s ticket service:
http://themeforest.net/refund_requests/new
In the refund request details please send us the purchase code from your purchase of Porto WordPress version.
Kind Regards,
Jonas