If you have a scene with 10 million+ polygons (a city block with interiors), you will need an RTX 3080 or 3090 with 12GB+ VRAM. Lumion loads almost everything into VRAM; if you run out, performance collapses.
: Enhanced performance for faster responsiveness when searching and placing objects. Atmospheric Effects Lumion Pro 12.5 Full
Updates to the Mass Move and Advanced Move effects allowed for smoother animations. If you have a scene with 10 million+