Fluorescent brush presets view - its hard to see what the strokes look like

I have a problem with how brush presets thumbnails colors are, please see the attachment. Instead of black on white view of preset thumbnail I have fluorescent green with blue, hard to see what the brush stroke look like. What can be done about it, is there any way to change that or reset that to black and white ?

Its Storyboard Pro 6 version on Windows 7.