Problem:
A project has both ACT 4*4 and ACT 2*2 ceiling tiles. I created the ACT 4*4 simply duplicating the ACT 2*2 but found out that I didn't really have any option to specify the grids shown on the floor plan even I tried to assign the hatch pattern to the newly created ACT 4*4 ceiling tiles. So it turned out that on the drawing, the ACT 4*4 had the exact grid distance same to the ACT 2*2, which obviously caused confusion.

It looks like the ceilings have embedded grids assigned to the only types available in Revit: ACT 2*2 and ACT 2*4.

Anyone has a solution to this?
Thanks!