Had the same issue. Are you getting a second error message once the game finishes loading telling you something is not in the right place. As the zip is shipped, the folder inside looks like something that can just be dragged into GameData, but the real folder that belongs there is actually two levels in. Instead of "Toolbar_x.x.x" you want to put "000_Toolbar" in your GameData folder. I did that, still got the message about it being out of date, but the icons appeared.