I’ve discovered that I can change the properties of a GUI which is located in CoreGui trough a normal script which is located in the Plugin model, however when I require a ModuleScript from that script and then subscribe to an event, the event’s callback does not get the same permission and manipulating a gui which is located in CoreGui will fail.
Proof:
“Inside of modulescript” → A method inside of a modulescript invoked by a script which is inside of a Plugin.
“Inside of the event” → In the same modulescript, invoked by a TextButton’s MouseButton1Down method which has been put into CoreGui by the script which required this modulescript.
Edit: Nor is the ‘plugin’ variable accessible in ModuleScripts which are required by a script in the plugin model.