Actually I figured it out. The button is for picking a color off of the desktop, or something other than the RWIE window. Not sure how to get a color from my picture on the bottom layer, onto one of the vector shapes (?) I guess I'll just have the photo open in another application window and sample from there.
Colo picker not working in Vector layer?
RWIE
As in the screenshot below.... I'm trying to make an avatar, but I can't seem to select color from my photo. If I use a raster layer, and the Pen Tool, then I can press Ctrl to pick a color. In a vector layer it doesn't work. Also the button shown (img) doesn't seem to do anything.
A bug -- or am I doing it wrong?