Note the "-n" so that you don't preserve your settings, which would be catastrophic moving between OpenWrt and Gargoyle.
That being said, it isn't supported by Gargoyle, until at least v1.15.x (which is currently in very slow development) and only if someone tests the image.
https://lantisproject.com/downloads/gargoylebuilds for the latest releases
Please be respectful when posting. I do this in my free time on a volunteer basis.