Update – fixed it, I was downloading old files that weren’t actually plug ins, I think I downloaded the latest ones here:
https://github.com/v002/v002-Open-Kinect/releases
https://github.com/Syphon/Quartz-Composer
If anyone is a newb like me, I dragged everything out of the parent folder and into the plugins folder in library. Make sure it’s the right library folder – not users!