So there is no v3.1 out! All I have is v1.31 and I get the realistic water and stuff. It isn't a separate patch it should come with v1.31 Try going to the terrain editing tab and click "day" for day mode then click "theme" and choose "Default Theme" not "SM Default". Those give me the better looking water and grass. Hope this helps. Also did you DL the tree packs form the SM website?