Define brush Preset

[coliny5045454]

For some reason define brush preset isn't working in Ps beta, works fine in std Ps. Don't know if I'm doing something wrong, or it's been turned off for some reason. Dec 23. Thanks CA Young uk windows 11

[Trevor.Dennis]

Hi Colin.

Have you got a raster (pixel) layer selected?

Does it have the preset you wish to define in black?  

Note: I have transparency around the preset in my screen shot, but it works on a white background.