Disclaimer: I'm no PPM wizard and I don't know the answers to most of your questions.. but perhaps this will point you in the right direction.
in reply to PPM download ppd without install
The 'rep' command will be useful to identify the repositories you are currently set up to use. Old style web interface repositories still exist, so you may want to see if any of those are set up in your PPM install. If so then you can browse through them with a web browser.
The 'prop' command looks interesting as well. You can run 'prop CGI' and find out information on the package, as well as what looks to be a fully qualified URL where you can probably download the package.
See also ActiveState's zip archive