So I've been playing with FW for a couple hours now and I've got to the point where I have researched the new custom tile improvements. They show up in the tech tree and in the Civopedia but for some reason none of my workers can build any. So far I've unlocked Nature Preserves, Communication Arrays, industrial Complexes and Eco-Commune. Is there anything obvious I'm missing or is something broken? If you need any pics for anything just ask