According to the latest tweet, and my own experience with this new version of the plugin, you no longer need the Cursive-specific instructions to replace :extra-deps with :extra-paths. Version 1.13.0 of the Cursive plugin fixes this. I'm using the EAP release of IntelliJ, though today I just updated to the Beta release and maybe that means things can work without the EAP channel.
Either way, :local/root works now with Cursive and you can update the readme.