sho row number in order-->show

Hi,

You can add the code:
<th class="title titletoggle">#</th>
before the code:
<th class="hikashop_order_item_name_title title"><?php
echo JText::_('PRODUCT');
?></th>
and the code:
<td><?php echo ++@$i; ?></td>
before the code:
<td class="hikashop_order_item_name_value">
in the file "show" of the view "order" for your frontend template.

Hi,

The discount is not an information stored in the order. So you can't display it.
The tax can be displayed like that:
<?php echo $this->currencyHelper->format($product->order_product_tax,$this->order->order_currency_id); ?>