Question about Prosper and overlays

Hello 

I have just started using Prosper (today), have only been using LaTeX a
few weeks, so apologies if this is very much a newbie question....

Running TeXlive and WinEdt on a Windows machine and using Prosper.

I would like the points in the second slide to dsiplay one at a time,
but they appear all at once.  I believe I am following the directions in
the documentation.  After entering the below code in WinEdt, I hit the
LaTeX button, then the dvi-ps button, then the ps-pdf button.  This all
works without error.  But when I open the pdf file, the whole second
slide appears at once.

I have looked at Making slides in LaTeX  with Prosper by Goualard and
Noergaard and at Making Presentations with LaTeX and Propser by Guha


Any help, or pointers to documents appreciated

START OF CODE

\documentclass{prosper}
\usepackage{pstricks, hyperref}
   \title{Graphs: The good, the bad, and the ugly}
   \subtitle{Graphical techniques for data exploration and modelling\\
      (and the R code to write them)}
    \author{Peter L. Flom}
    \institution{National Development and Research Institutes,  
Inc.\\
     www.peterflom.com} 
    \email {[email protected]} 
\begin{document}
\maketitle
\overlays{6}{
\begin{slide}{Questions to ask}
 \begin{itemstep}
  \item What do graph?
  \item Why do you want to graph it?
  \item Who is going to see it?
  \item How are they going to look at it?
  \item When do you need it done?
 \end{itemstep}
\end{slide}}
\end{document}


END OF CODE

Peter

Peter L. Flom, PhD
Assistant Director, Statistics and Data Analysis Core
Center for Drug Use and HIV Research
National Development and Research Institutes
71 W. 23rd St
www.peterflom.com
New York, NY 10010
(212) 845-4485 (voice)
(917) 438-0894 (fax)




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