What do you mean it hardened? In the little tube? Or do you mean you mixed your Z2 and ZFX before you prepped the truck? Thats a no-no! The Z6 spray is not a substitute for wax, I'd just get some new Zaino asap or use a store-brand wax in the interim.
Not to mention Zaino kicks ***. Don't listen to all the Meguiars bull****. That's all I see when someone brings up zaino. And when someone mentions Mobil 1, a bunch of people always have to say that AMSOIL is the greatest.