Have a look at the flat sides of that shape > the face that was extruded, you will see that it is divided into sections. When you try a texture allignement on wall or floor, whatever it's never ok. i mean, the texture looks still broken and difficult to allign. As hard as you try, you think, well it will be ok and now i do the lighting part. Then surprise, these sections are completely wrong liten you can clearly see the sections, some are darker some are very bright and other sections are even completely black. Now for your convenience, there's such tool in the contextual menu for the brush you need to align. First thign to do for it to work is to align the textures to floor and to wall like you want. Then rightclick an edge of that brush. select polys > polys merge. when that brush or if you have more brushes to do are done, just make a geometry rebuild. rebuild the light and admire your work. by doing so, remark that instead of having 4 or 6 separated polygons on that face, you only have one for that face beeing the floor or wall, this also means less data in the mapfile, so file is smaller. first, when the shape is made, the face has multiple polygons in it, and as you can see, even after a Wall-alignement it's still not aligned correctly, you may try it manually, but beware, the lighting will reveal it's polygons, this is useless. You can now either select wireframe view or select one of the surfaces with shift, this will show the wireframe also. Then RIGHT click an edge of the shape here this is a substract. This will bring up the contextual menu for that brush, here you should see this menu Polygons > Merge. Select Merge. This , as it says, will merge all the separated polygons into one big polygon, and this has as effect to » - adjust the texture at a correct level. - lighting will be done correctely on only one big surface - cos it became one surface, the data is reduced to one surface instead of 10 surface data. - you can select it by only one click, instead of all separated.