I’ve got a couple questions for you. Is the event sign-up you’re referring to related to these APIs? Introducing the New Experience Event APIs
Also is the “CloseButton” you’re referring to a button that you have created, or is it part of this prompt that we provide?
Main reason I ask is because the error message here is actually a bit ambiguous on the engine’s side “PlayerGui” really just means “PlayerGui”, or “CoreGui”.