I switched the windows theme to high contrast (white on black) and back to windows default (white/blue) and the background for the properties/layers toolbars are stuck as black.
I have gone into File/Properties/Rhino Options/Appearance/Colors and changed it back to default and it fixes it until I click OK.
I’m on windows 7 professional
i5, 32gb ram, 64 bit
Version 5 SR12 64-bit