veiwing Molecular orbitals

   I am a new NWchem user.  I am able to use DPLOT to generate a cube file for the molecular orbital I am interested in plotting/viewing, but any other software I've tried to use to open the cube file cannot read it.  I have tried Avogadro, Molekel, and Molden.  Is there a different way I can be exporting/creating my MOs or is there a different software I could use to open the cube files I have.