For the curious; that's just by adding the "apt-setup/proposed=true" boot parameter as you boot from an alternate CD -- you don't need to download any special installer image (you don't need the first link in the wiki page mentioned above).
For the curious; that's just by adding the "apt-setup/ proposed= true" boot parameter as you boot from an alternate CD -- you don't need to download any special installer image (you don't need the first link in the wiki page mentioned above).