Download the maps you want. Then put the map.bsp into you esf/maps directory and and if there is sprites or models in then put them into the esf/sprites and esf/models. If there is a gfx/env file in then unload it into the esf/gfx/env directory.
well this happened to me before you are probebly instaling it wrong but your probebly not all you have to do is delet it and reinstall it then go to creat server look for ur map then click on on do not put any bots on it or it will mess the map up. then you will have to reinstall it again.