1.Right Click on the Cube and make room H=4095, W=8192 and D=8192
2.Subtract the Cube
3.Open the Texture browser and select a texture and apply to the 4 Walls.
4.Next go to the Tab for Actor Classes and open Info. You will see Zoneinfo. Highlight it then Minimize the Browser.
5.RightClick in the center of the Top Grid and choose Add Zone Info Here.
6.RightClick on the ZoneInfo Icon placed in the Map, and choose ZoneInfo Properties.
7.Click the + sign next to ZoneInfo.
8.Click on bterrainzone and set to True.
9.Click on the + sign next to ZoneLight
10.Set AmbientBrightness to 128
11.Close the ZoneInfo Properties.
12.At this point do a Build All
13.Open the Texture browser and choose a texture for your terrain then minimize
14.Click on the Terrain Editor on the left toolbar.
15.Click on the New at the very bottom left hand corner.
16.Type in MyLevel for Package, MyLevel for Group and Name can be anything you want.
17.You should see a Yellow Line in the 3d window and a TerrainInfo0 under the Terrains tab. Also you should see Heightmap info to the right of that.
18.Click on the Layers Tab.
19.Select the Top Undefined Layer.
20.Click on the New Button.
21.Package and Group are the same as before—MyLevel
22.The Name must be different than the first one that you used to create the Heightmap or it won’t work.
23.The AlphaFill I click on the button to the very rightmost side. It will bring up a color chooser. I slide the slider all the way up until it is white. R=255, B=255 and G=255. The Alpha Layer is still at 0.
24.Click Ok.
25.Under the Tools options highlight Select. Then click on the Misc Tab.
26.Put a Check Mark in Use Entire Heightmap. Then click on the Build button. Voila Terrain.
27.You can do a Build All here also.
28.Close the Terrain Editor.