If the character is a simple cr2 file just put it in your characters directory in PoserRuntimeLibrariesCharacterAny file you want. Sometimes textures may already have been saved pre-applied and in that case Poser will ask you for them. You don't need to follow the readme here. Place the texture wherever you like to keep them and point Poser to it. You can then resave so Poser remembers the path. Generally if a download has an .obj or .pcf, .uvs file then instructions are usually provided as well. If not then check back at the forum :)