There was a lack in dblatex: slides xsl stylesheets from db2latex has been nether added.
So, I released an adaptation of them, and included them in my own version
I will obviously send the patches soon to the upstream...
First, install this dblatex version (by running "python setup.py install" in the inflated directory, or by installing the debian package).
Now, you can use dblatex as usual, or type "dblatex -T slides myfile.xml", or "dblatex -T gt-slides myfile.xml", assuming "myfile.xml" is conforming to "DOCBOOK slides DTD" from Norman Walsh.
If you want another Prosper slide style, then add "-P latex.slides.customclass=the_style_without_PPR".