You mean the flat icon set? The lovely flat icon set? These have now been included with 4.2 which I’m delighted about, as I have been manually installiing the flat icons for quite a while.
[Update: as @oweng points out in the comments, your screenshot seems to be concerned with some of the UI elements, rather than the icon set per se. Could you perhaps clarify in words in your question exactly what the problem is? “Icons” suggested to me the Sifr set, and my answer goes on in that vein. My sense tallies with @oweng’s, that the toolbar bits you might have in mind are OS dependent, rather than a LibO issue. How did you install 4.2, btw? That would help to know.]
I haven’t got 4.2 yet – although I’m looking forward to it – but you can select your icon set from
Tools > Options > View then pick your icon set from “Icon size and style” (second item in left-hand column of options):
I thought this was not supposed to be the default setting, though, so I’m puzzled you got this “out of the box”.