Interesting. I downloaded the test BIQs, and have been able to confirm that there is a unit there that the Firaxis editor does not display. Still have some investigation to do, though; I've documented it in the bug tracker to ensure it doesn't get forgotten. I am curious what the process was to create the barbarian unit, beyond that the city needs to be owned by a player. Any units placed on a city tile should have the same owner as that city, so it is rather puzzling. The Oracle/OpenJDK Java 11+ builds are not compatible. However, I have had good success running the Liberica Java builds. If you choose the "Full JDK" (if you need developer tools) or "Full JRE" package, it includes JavaFX (which the editor requires, and was removed in the Oracle Java 11 build), and the editor should work out of the box; I have verified this with their Java 13 build. Alternately, the Windows XP Build includes a bundled Java 8, that the editor will use but will not be a system default. If going that route, the jre1.8_111 folder, Editor_XP.bat file, and (optionally) XP_laucher.vbs file can be copied over to a download of a newer version to have them also use Java 8, independent of your system Java version. There also is a macOS build for Java 11. This is a one-off so far, however, as there hasn't been further demand for it. I also have only tested the editor on Macs through High Sierra (which is what my 2010 Mac Mini runs), and cannot guarantee Catalina compatibility. It has been a couple years since Java 11 came out, and at the time it proved to be a huge pain to get the editor working with both Java 8 and Java 11; the one-off custom-built Mac version was the only success of that effort, and it looked like success would require building on all OSes (Mac, Windows, Linux) separately rather than just once and having it run anywhere, which would add considerable overhead to a project that is already a bit low on development time. Since at the time Java 8 was still receiving updates, and not auto-updating to Java 11, I decided to go back to focusing on Civ-related features until it came up on the radar again. It might be time to revisit it and see if there is a less painful way forward now than when I last looked at it. It does look like my hosted download links broke after I combined a few virtual private servers earlier this summer. I've added a note to update those. I have not. I have explored barbarian cities a little bit, and there are a few threads in C&C discussing them... and it looks like I was able to find the most recent one here.