Mask overlay is not showing. "Show selected mask overlay" checked. Changing to other colors with Shift-O does not fix the problem. Dodge/Burn effects also do not work. I don't see this mentioned in any post and, of course, Adobe provides no way to contact them for technical support (evidently when you're perfect there is no need to provide technical support). Can anyone help me since Adobe won't?
-The Overlay is not visible until the Brush (or Gradient) has been applied to the photo.
-The Brush (Gradient) panel has been minimized (to the 'Amount' slider) and sliders in the Basic panel are being adjusted.
-The Overlay color by [Shift+O] has Red, Green, White, Grey. The white & grey overlays may give the appearance of having brushed an area when, in fact, the brush sliders are all set to zero adjustment.
-The "Dodge & Burn" Brush Presets are very minimal slider adjustments- make a change of the sliders to suit your image.