how to rate home share songs on my ipad

I have home sharing activated on my home computer and can play the music through my ipad 1. But can't seem to find a way to rate songs as I play them

I click on the square icon beside the song playing and then more at the bottom after that but it seems to bring up all songs by the artist that is playing. As I only want to rate that individual song this doesn't work.

Any ideas ?

Footah