Don't get me wrong, I am a dedicated KiCAD user but they do that every major release. Every. Single. Time. There is always some huge hassle with existing libraries. I spend way too much time dicking around with libraries when I upgrade so, for now, I'm sticking with V 8. Nothing I have seen in 9 is so compelling that I just HAVE to upgrade. Maybe version 10 project should have a goal of not breaking designs made with earlier versions. Except for libraries, they have done reasonably well. I'd give them a B+ but with libraries, C---.