Hi raimiux
Do you mean that the link of product you added doesn't work?
Make sure that you have a menu item type of that component (Virtuemart - for example) that product belongs to and also access Backend >> Components >> JA Megafilter >> Index that filter.
If it still doesn't work, you can share the login info of your site and tell me the product that is not linkable, I will check for you.
Regards