Sorry folks - started new thread by mistake.
Surprised some people found this easy. I have been struggling for a long time with the top left corner, and still don't have 2d or 13a. I think 2d may be something that I am using right now, although I can't parse it, but that would leave me stumped on 13a.
I thought that 23d was a clever clue. Answer obvious, but parsing difficult until the penny dropped.