I think there appears to be some confusion :
ATV, open PLI, opendroid etc are officially supported images for zgemma (see
http://zgemma.org/downloads.html), VIX is another image but it does not officially support zgemma. These images will work fine (official ones at least) which you need to setup and install plugins yourself.
Then you have builds such as Wooshbuild Infinity, Grogbuild FreeRange, Ipab, WilloBuild build and Dsayers to name a few. These are as the name suggests, box setups that people have built and then shared, they all require one of the above images. Wooshbuild Infinity, Ipab, Dsayers all are for ATV, WilloBuild for VIX, Grogbuild with either ATV or VIX.
You should not confuse the two, the box needs an image installed to run, the user wants a build installed as they can't be ***** to set the box up from scratch.