I'm playing around with the tech tree a bit, moving some things around, and something that really bothers me is it's so easy to beeline techs. So I thought of adding a requirement for moving among the rings. You can't research anything in the second ring until you have so many techs in the first ring, so each ring is like an era. I would actually like to make each ring an era (I'll be moving techs around and making a fourth ring) and make it a requirement that you need so many techs per era. Unfortunately I'm not too skilled in modding (yet, I'm working on it), and I was wondering if anyone could give me advice for how to go about this.