A number of research topics (e.g. Atmospheric cleansing) are greyed out and I don't know why. Some have "disabled for beta" but others don't have this message and I don't know if this is intentional, a bug or if I'm missing some dependency and the display is not making that clear.
In GC3 technology research is divided into three "Ages" (shown at the bottom of the research screen). You can't research a technology in a given age until you've entered that age. This is not all clear to the new player, and it is especially unhelpful that clicking on a tech to research it when you can't gives you no message whatsoever, it just selects a different tech that you can research.