Hi,
To change the size of the popup, you can edit the view "address / listing" via the menu Display > Views.
And replace "760","480" in the code:
<?php echo $this->popup->display(
'<span class="icon-32-new" title="'. JText::_('HIKA_NEW').'"></span>'. JText::_('HIKA_NEW'),
'HIKA_NEW',
hikashop_completeLink('address&task=add',true),
'hikashop_new_address_popup',
760, 480, '', '', 'link'
); ?>
If you need to change the content inside the popup so you have to add css in the artisteer template css file.