Yo he dado con ello desde este post en el foro en inglés que te lleva al francés: http://www.prestashop.com/forums/topic/316668-hook-product-logo-payments-in-product-page/
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Dear all, I found the solution, and it's a presta bug it seems. ( sure)
In my case (prestashop 1.6.0.4 ) this solution works.
Thanks to the French guys :-)
http://www.prestasho...t/#entry1603896
Change store for shop in the \modules\productpaymentlogos\productpaymentlogos.php
..and works !"