For now I found a different solution that's OK for my needs. In order page, the admin side, each has a picture, the name is clickable and will redirect to the product page.
This is the procedure:
/admin/order.php
@about line 490 immediately after the FOR cicle: for ($i=0, $n=sizeof($order->products); $i<$n; $i++) {
write:
PHP Code:
$url = $order->products[$i]['id'];
$name = $order->products[$i]['name'];
@about line 500 replace this:
PHP Code:
echo ' <tr class="dataTableRow">' . "\n" .
' <td class="dataTableContent" valign="top" align="right">' . $order->products[$i]['qty'] . ' x</td>' . "\n" .
' <td class="dataTableContent" valign="top">' . $order->products[$i]['name'];
with this:
PHP Code:
echo ' <tr class="dataTableRow">' . "\n" .
' <td class="dataTableContent" valign="top" align="right">' . $order->products[$i]['qty'] . ' x</td>' . "\n" .
' <td class="dataTableContent" valign="top">' . "<a href=http://www.nameofyourstore.com/index.php?main_page=product_info&products_id=$url>$name</a>" . '<br>' .
zen_image(DIR_WS_CATALOG . DIR_WS_IMAGES . zen_get_products_image($order->products[$i]['id']), SMALL_IMAGE_WIDTH, SMALL_IMAGE_HEIGHT);
This is the result:

The photos can be seen properly with imagehandler.
The links to the products work only if the product is active.
When I have some time, I'll find (I hope) the solution also to insert the link in the admin confirmation email. 
I hope to be helpful and sorry for my english (sponsored by google translate hahahaahahhahaha)
Bookmarks