When a SimulArt item is added to a WooCommerce cart, there is no link back to the product details page because the product is set as "hidden" to prevent other users to see it. To change this behaviour, you need to edit the file /wp-content/plugins/woocommerce/templates/cart/cart.php
Around line 44, replace
$product_permalink = apply_filters( 'woocommerce_cart_item_permalink', $_product->is_visible() ? $_product->get_permalink( $cart_item ) : '', $cart_item, $cart_item_key );
by
$product_permalink = $_product->get_permalink( $cart_item );
This will force the cart links for SimulArt hidden items without making them visible in pages and searches.