Muchas gracias por contestarme. Aquí tienes lo que pides, ¡ojalá veas el problema!.
Contenido del htacces de la carpeta del prestashop.
# .htaccess automaticaly generated by PrestaShop e-commerce open-source solution
# WARNING: PLEASE DO NOT MODIFY THIS FILE MANUALLY. IF NECESSARY, ADD
YOUR SPECIFIC CONFIGURATION WITH THE HTACCESS GENERATOR IN BACK OFFICE
# http://www.prestashop.com - http://www.prestashop.com/forums
<IfModule mod_rewrite.c>
# URL rewriting module activation
RewriteEngine on
# URL rewriting rules
RewriteRule ^([a-z0-9]+)\-([a-z0-9]+)(\-[_a-zA-Z0-9-]*)/[_a-zA-Z0-9-]*\.jpg$
/decoracion/img/p/$1-$2$3.jpg [L]
RewriteRule ^([0-9]+)\-([0-9]+)/[_a-zA-Z0-9-]*\.jpg$
/decoracion/img/p/$1-$2.jpg [L]
RewriteRule ^([0-9])(\-[_a-zA-Z0-9-]*)?/[_a-zA-Z0-9-]*\.jpg$
/decoracion/img/p/$1/$1$2.jpg [L]
RewriteRule ^([0-9])([0-9])(\-[_a-zA-Z0-9-]*)?/[_a-zA-Z0-9-]*\.jpg$
/decoracion/img/p/$1/$2/$1$2$3.jpg [L]
RewriteRule ^([0-9])([0-9])([0-9])(\-[_a-zA-Z0-9-]*)?/[_a-zA-Z0-9-]*\.jpg$
/decoracion/img/p/$1/$2/$3/$1$2$3$4.jpg [L]
RewriteRule ^([0-9])([0-9])([0-9])([0-9])(\-[_a-zA-Z0-9-]*)?/[_a-zA-Z0-9-]*\.jpg$
/decoracion/img/p/$1/$2/$3/$4/$1$2$3$4$5.jpg [L]
RewriteRule ^([0-9])([0-9])([0-9])([0-9])([0-9])(\-[_a-zA-Z0-9-]*)?/[_a-zA-Z0-9-]*\.jpg$
/decoracion/img/p/$1/$2/$3/$4/$5/$1$2$3$4$5$6.jpg [L]
RewriteRule ^([0-9])([0-9])([0-9])([0-9])([0-9])([0-9])(\-[_a-zA-Z0-9-]*)?/[_a-zA-Z0-9-]*\.jpg$
/decoracion/img/p/$1/$2/$3/$4/$5/$6/$1$2$3$4$5$6$7.jpg [L]
RewriteRule ^([0-9])([0-9])([0-9])([0-9])([0-9])([0-9])([0-9])(\-[_a-zA-Z0-9-]*)?/[_a-zA-Z0-9-]*\.jpg$
/decoracion/img/p/$1/$2/$3/$4/$5/$6/$7/$1$2$3$4$5$6$7$8.jpg [L]
RewriteRule ^([0-9])([0-9])([0-9])([0-9])([0-9])([0-9])([0-9])([0-9])(\-[_a-zA-Z0-9-]*)?/[_a-zA-Z0-9-]*\.jpg$
/decoracion/img/p/$1/$2/$3/$4/$5/$6/$7/$8/$1$2$3$4$5$6$7$8$9.jpg [L]
RewriteRule ^c/([0-9]+)(\-[_a-zA-Z0-9-]*)/[_a-zA-Z0-9-]*\.jpg$
/decoracion/img/c/$1$2.jpg [L]
RewriteRule ^c/([a-zA-Z-]+)/[a-zA-Z0-9-]+\.jpg$ /decoracion/img/c/$1.jpg [L]
RewriteRule ^([0-9]+)(\-[_a-zA-Z0-9-]*)/[_a-zA-Z0-9-]*\.jpg$
/decoracion/img/c/$1$2.jpg [L]
RewriteRule ^([0-9]+)\-[a-zA-Z0-9-]*\.html
/decoracion/product.php?id_product=$1 [QSA,L]
RewriteRule ^[a-zA-Z0-9-]*/([0-9]+)\-[a-zA-Z0-9-]*\.html
/decoracion/product.php?id_product=$1 [QSA,L]
RewriteRule ^([0-9]+)\-[a-zA-Z0-9-]*(/[a-zA-Z0-9-]*)+
/decoracion/category.php?id_category=$1&noredirect=1 [QSA,L]
RewriteRule ^([0-9]+)\-[a-zA-Z0-9-]*
/decoracion/category.php?id_category=$1 [QSA,L]
RewriteRule ^([0-9]+)__([a-zA-Z0-9-]*)
/decoracion/supplier.php?id_supplier=$1 [QSA,L]
RewriteRule ^([0-9]+)_([a-zA-Z0-9-]*)
/decoracion/manufacturer.php?id_manufacturer=$1 [QSA,L]
RewriteRule ^content/([0-9]+)\-([a-zA-Z0-9-]*)
/decoracion/cms.php?id_cms=$1 [QSA,L]
RewriteRule ^content/category/([0-9]+)\-([a-zA-Z0-9-]*)
/decoracion/cms.php?id_cms_category=$1 [QSA,L]
RewriteRule ^pagina-no-encuentra$ /decoracion/404.php [QSA,L]
RewriteRule ^direccion$ /decoracion/address.php [QSA,L]
RewriteRule ^direcciones$ /decoracion/addresses.php [QSA,L]
RewriteRule ^autenticacion$ /decoracion/authentication.php [QSA,L]
RewriteRule ^mas-vendidos$ /decoracion/best-sales.php [QSA,L]
RewriteRule ^carro-de-la-compra$ /decoracion/cart.php [QSA,L]
RewriteRule ^contactenos$ /decoracion/contact-form.php [QSA,L]
RewriteRule ^descuento$ /decoracion/discount.php [QSA,L]
RewriteRule ^estado-pedido$ /decoracion/guest-tracking.php [QSA,L]
RewriteRule ^historial-de-pedidos$ /decoracion/history.php [QSA,L]
RewriteRule ^identidad$ /decoracion/identity.php [QSA,L]
RewriteRule ^fabricantes$ /decoracion/manufacturer.php [QSA,L]
RewriteRule ^mi-cuenta$ /decoracion/my-account.php [QSA,L]
RewriteRule ^nuevos-productos$ /decoracion/new-products.php [QSA,L]
RewriteRule ^carrito$ /decoracion/order.php [QSA,L]
RewriteRule ^devolucion-de-productos$ /decoracion/order-follow.php [QSA,L]
RewriteRule ^pedido-rapido$ /decoracion/order-opc.php [QSA,L]
RewriteRule ^order-slip$ /decoracion/order-slip.php [QSA,L]
RewriteRule ^contrasena-olvidado$ /decoracion/password.php [QSA,L]
RewriteRule ^promocion$ /decoracion/prices-drop.php [QSA,L]
RewriteRule ^buscar$ /decoracion/search.php [QSA,L]
RewriteRule ^mapa-del-sitio$ /decoracion/sitemap.php [QSA,L]
RewriteRule ^tiendas$ /decoracion/stores.php [QSA,L]
RewriteRule ^proveedores$ /decoracion/supplier.php [QSA,L]
</IfModule>
# Catch 404 errors
ErrorDocument 404 /decoracion/404.php
<IfModule mod_expires.c>
ExpiresActive On
ExpiresByType image/gif "access plus 1 month"
ExpiresByType image/jpeg "access plus 1 month"
ExpiresByType image/png "access plus 1 month"
ExpiresByType text/css "access plus 1 week"
ExpiresByType text/javascript "access plus 1 week"
ExpiresByType application/javascript "access plus 1 week"
ExpiresByType application/x-javascript "access plus 1 week"
ExpiresByType image/x-icon "access plus 1 year"
</IfModule>
FileETag INode MTime Size
<IfModule mod_deflate.c>
AddOutputFilterByType DEFLATE text/html
AddOutputFilterByType DEFLATE text/css
AddOutputFilterByType DEFLATE text/javascript
AddOutputFilterByType DEFLATE application/javascript
AddOutputFilterByType DEFLATE application/x-javascript
</IfModule>
captura htacces raiz del host:
# -FrontPage-
IndexIgnore .htaccess */.??* *~ *# */HEADER* */README* */_vti*
<Limit GET POST>
order deny,allow
deny from all
allow from all
</Limit>
<Limit PUT DELETE>
order deny,allow
deny from all
</Limit>
AuthName unsolouso.es
AuthUserFile /home/fkqzscpw/public_html/_vti_pvt/service.pwd
AuthGroupFile /home/fkqzscpw/public_html/_vti_pvt/service.grp