How can I create a ceiling grid with a hole in it?
Planning ahead, the ceiling grid will be created from a Space. First place a small shape to represent the ceiling grid hole within the larger area that will be used to create the Space. When creating that Space set the Place By method to Flood and enable the Minimum Hole Size option set to an appropriate value (less than the small shaped placed previously).
Using the Ceiling Grid tool select the Space above which will create the ceiling grid with a hole inside it: