Color picker does not work when choosing a colour for a "stroke" from the library or when selecting colour within "layer style's"

Does anyone else have this problem? Colour picker is not available or does not work within layer styles. I am unable to select a colour from the library. I have the same problem when i'm adding a stroke to a shape. The library colours only work when i need to "fill" the shape. But it does not work when i want to change the colour of the stroke. Could you please advise?