Hi,
About resizing grids, I guess that's because they all have the same attributes and you're adding/removing fixtures. The best way is to use the linked layout option when duplicating your grids. However, you can't decide to link grids after... There's a new option coming in the next beta to link only the actual grid size and attributes positions (attributes can still be configured).
If you're tech-savvy, you can edit the project file directly and do the search and replace you need.