Can’t find the URL Settings in the New WP-Ecommerce 3.8x ?
3.7x had a simple solution in the admin panel, however the new version doesnt.. SO:
Go to this url (replace yourdomain.com with your own domain)
Then find product_list_url, shopping_cart_url option, transact_url, and user_account_url option. Change the value with your new page url.