When I transfer the group to another .blend (by append or taking the object with me) then the spread only switches back and forth between active and deactivated, even though I don't change anything in the group. Do you know what is the reason for this?
i'll be honest... It took me four attempts before it worked at all. The spread and the not-understanding of the "map range" kinda kill me here xD
Sorry, it was because you have to enable Ambient Occlusion on Eevee in the new file too. Maybe this info will help others too ^^