Hi,
As for the character not taking radial damage, can you make sure at least one component (preferably the mesh) in your character actor blocks the Visibility Collision Channel? The radial damage node specifically states that it will only damage ‘visible’ actors, but for some reason the default presets of ‘Pawn’ and ‘CharacterMesh’ that the default character components use both ignore that channel, which might be the source of your problem.
Kind regards,