How on earth do you get away doing this! I guess you are very much braver than most or the railway station is very tolerant or has few cameras and police around!
I guess it's possible if one knows when there are few travelers around!
What are the laws where you are. Here it's considered illegal but actually there has to be some complaint that the nudity disturbed someone else there. Still it would not actually be illegal unless one oersisted despite the objections of others in that same location.
My second visit will be about the picture, but first I wanted to find out about how one goes about staging such a picture, assuming that it's not constructed of two separate images