Ok, so I was able to get a technology to appear in Column 18 by making it a part of the Information Era. I then added in my Terran Era, but didn't give it any technologies. The tech tree showed in both of these cases. Once I assigned this new tech to this new era, then the tech tree shows up blank like that and, curiously enough, when I choose which tech to research, it says that the tech that I put into this new era was just finished!