Enable GUILayout shouldn't affect event sending, it just sets useGUILayout:
https://docs.unity3d.com/ScriptReference/MonoBehaviour-useGUILayout.htmlAre you using any GUILayout actions?
If you're not using any GUI or GUILayout actions you can safely delete PlayMakerGUI. Also, uncheck
PlayMaker Editor > Preferences > Auto Add PlayMakerGUI to Scene.
PlayMakerGUI is also currently needed to draw State Labels. We will be transitioning to a new uGUI solution for State Labels and other debug info soon, at which point we'll start phasing out PlayMakerGUI.
I'll add more info about PlayMakerGUI to the docs.