Comments by m.qayyum (Top 3 by date)

Yes you can create custom action dll in c# and use it in Advanced Installer.

If you own the setup than, you can save settings in registry like in that tutorial and can read those values easily from registry using c#. And if you don't own the installer then you are left with only two option either you read the setup's text using win32 api. (Example here http://www.dreamincode.net/forums/topic/66140-scraping-the-text-from-another-application-with-win32-api/ ) or just use what is available from that installer (logs or whatever they provide).