Hi,
The easiest way to change the popup size is to edit the file "administrator/components/com_hikashop/helpers/cart.php"
In the function "getJS()" just replace the value of "x" and "y" in the lines:
'<a rel="{handler: \'iframe\',size: {x: 480, y: 140}}" id="hikashop_notice_box_trigger_link" href="'.hikashop_completeLink('checkout&task=notice'.$url_itemid,true).'"></a>'.
'<a rel="{handler: \'iframe\',size: {x: 480, y: 140}}" id="hikashop_notice_wishlist_box_trigger_link" href="'.hikashop_completeLink('checkout&task=notice&cart_type=wishlist'.$url_itemid,true).'"></a>'.
Be careful, when updating, the changes will be lost.
To redirect them, in the view "checkout / notice" via the menu Display > Views, you have to change the line:
setTimeout( 'window.parent.hikashop.closeBox()', <?php echo (int)$this->config->get('popup_display_time',2000);?> );
To:
setTimeout( 'window.location = "http://www.mozilla.org"', <?php echo (int)$this->config->get('popup_display_time',2000);?> );