Looks really impressive, nice work.
Regards the nav mesh question above, yeah it would be a really nice feature. I’d suggest NavMeshRenderingComponent.cpp would be the place to start looking if you wanted to implement this.
If you could extend the system to overlay multiple masked/translucent layers of background that could be toggled on and off individually, that would open up some really nice possibilities. Don’t want to suggest this is lacking as it is though - it’s clearly been a lot of work and looks very well designed. Hope it’s successful.