Animation and Rigging Tools: FAQ, Known Issues and Feature Roadmap

You are posting in a thread I created, for support on a toolset I wrote, which happens to be named ART (animation rigging toolkit), that ships with the engine. It’s not a huge leap.
Also, in my 4.12 on the launcher, I’m not seeing anything like what you’re seeing. Afraid I can’t help you and this probably isn’t the thread if it’s not about the animation and rigging tools.