I suppose you mean the huge waves that not only look real graphically, but also change the height of the water and stuff?
Well, for that, you’ll need to extract the W3D models for water, all titled like this: wtr_arnor wtr_ettenmoors Then, create your ocean using the lake/ocean tool. In the Options box, under FX Water Options, uncheck the Enable FX Shaders option. Then agina click it, and this time a dialog box will open asking you to locate the W3D files. Select your extracted W3D files and click OK. Your new textured ocean should be visible. Out of all the W3D water files, only a few have waves, such as Ettenmoors, Forlindon and Gondor W3D water models (wtr_ettenmoors, wtr_forlindon, wtr_gondor). Hope this helps.
