Create a graphics folder (if you don't have one) in FM 13 in the same place where they are in FM 12, then either cut/copy and paste them into the graphics folder.
My Documents>SI>FM 13>Graphics. But you MAY have to start a new save to make them work I can't remember
As far as I'm aware skins WON'T work (unless someone says otherwise of course).
Competition name fix works as well btw