The size and shape of the radial filter do not appear on my screen. However, some effects appear, although not the ones I want. Also, the invert mask seems to work in reverse to the way that it normally does.
That problem is resolved. El Capitan seems to work fine now. I still cannot see the diagram for the radial adjustment tool, and so cannot place the effect precisely where I want it. The effect is imparted to the image.