Finally i've lauched my first version of my mod yesterday! the next version will deal with tech tree. which AFAIK right now it progressed TOOOOO fast and not really reasonable (Actually I like Civ5 tech tree more). Also there's a mod that deals with tech tree. But i want to include tech (and civics) reorganizations in the next version instead. 1. What are XML files needed to add 2. Codes needed to modify or reorganize tech tree? like if I want The Wheel to require Archery, and Horseback Riding to require The Wheel. What are the differences between syntax 'update', 'replace', and 'delete'? 3. Will it takes effects on tech tree layouts too?