Customize UI Buttons Not Showing Up
Please upgrade your program. This is free for registered users, and you are missing years of features and bug fixes. Obsolete program versions are not supported.
Non-standard brushes assigned to an interface will not show up on the interface until they are loaded into the program, via Lightbox or otherwise. Only the brushes in the startup data files load with the program. You can add brushes to the startup files, but do it sparingly–there are performance implications. It would be best to do this only for brushes you’ll be using all the time. More situational brushes you won’t be using every session should be loaded on demand through Lightbox.