Since there is lack of information on how to operate with HPO, I strongly recommend checking the build-in Help manual or documentation, one that you could find by accessing built-in functions like Help > Contents or by accessing the installation directory where the HPO's files are stored. The documentation files might come in various ways like PDF, CHM, TXT, DOC, RTF or even HLP files. I suggest you look in the installation directory for these files to see what could be the problem to your errors.
