This is installation instruction for Duokan lite. The download link from original post (the very first post on this thread) is dead now, but I did try with different version of Duokan lite and installation failed.
For Duokan lite it is necessary to have previously installed launchpad (with uninstalled jailbreak), but for full Duokan 2012 version (from original Chinese website) dated 28.12.2012., user doesn't have to install neither jailbreak nor launchpad.
I'm downloading now this latest version of Duokan 2012 and will see if it is working on firmware 3.4.
To be honest, even if it's working I'm not sure I would manage to navigate through Chinese menu.