Hey, I used https://brunoherbelin.github.io/vimix/ for a short experimentation at Geekfaeries but the mapping was pretty simple (mapping a big fire on a castle and then a spinning mandala, single projection). Vimix helped me to position/adjust the video size and blending with the logo, and manage fading between both visual modes.

@davidrevoy thanks for the tip, will try it out.