Command line problem

 Environment:

 
   Windows XP Pro, SP3
   WordPerfect 9.0.0.896
   PDFCreator 0.9.9
 
When I print to PDFCreator from within WordPerfect, the PDF is usually created successfully.
 
But when I invoke PDFCreator from the command line, using /IF and /OF, PDFCreator starts and then stops immediately with no output and no messages. I would prefer to use the command line method.
 
When I use the command line method, am I doing something incorrect? How can I use the command line method successfully?
 
Thanks in advance,
Adrian