Hi everyone, i'm experiencing a problem with Update3D function : if I call it on a light reference, the light flashes creating a very annoying effect. How can i fix this?

Thank you in advance for help

Update3D reloads the model for the reference it is called on, which necessarily involves a brief delay between the old model disappearing and the new one appearing.
If you are trying to change the light's color without changing the actual model, you might want to check if NifSE provides any commands for doing so. If it doesn't I'll try to find time to see how feasible it would be to add a command to do so.