Lighting and the ring light are actually something I;m still learning, and it's ongoing... I don't always enjoy using auto focus, but when I'm doing self portraits, it must be auto focus.
The ring light changes how the exposure looks, and can often end up being a long or longer exposure, so blurring, and motion blur can happen.
But, at least I still got a my ring light.
Many people claim that powder makeup looks bad in photography, however I've found it to look rather good with the ring light.