First thing I do when importing a .obj file is try to bring it to real world scale - this often alleviates many bump issues or at least lessens them. Second thing I do on human figures is applying the SkinVue script. This works not just on imported Poser files, but exported .obj files, as long as the .obj file contains a supported human figure mesh with it's materials in tact i.e. no merging of identical materials on import. I'm not sure what version of Vue you are running, but SkinVue is a lifesaver as it not only fixes many of the annoying issues with imported skin textures, but makes them come alive with realism.