FYI: Just updated to 0.17.2 and all of my catlists disappeared: nothing rendered in delivered code. I tried removing references to the custom template, no luck.
Downgraded to 0.17.1 and 0.17, still nothing.
Downgraded to 0.16.1 and they're back.
My custom templates are in my parent theme folder inside /list-category-posts/.
Still looking into it ...