Settings | Griddy Docs

In the Motion Dock, enter Edit layout and double-click Griddy’s slot. You can also right-click its slot and choose Module settings. Leave layout mode after closing settings to use Griddy again.

These settings are the grid Griddy puts on a comp that has none. Griddy also updates them every time you use a grid, so they always hold the last grid you used.

Changing them doesn't touch a comp that already has a grid.

Griddy's settings: Units set to Pixels, Gutter 20, and Top, Right, Bottom and Left Margin 80, each with its description.

Setting	Default	Range	Behavior
Units	Pixels	Pixels or Percent	Whether the gutter and margins are in pixels or a percent of the comp, or of the layer for a grid inside a layer.
Gutter	20	0 to 2000	The space between columns and between rows.
Top Margin	80	0 to 4000	The space above the cells.
Right Margin	80	0 to 4000	The space right of the cells.
Bottom Margin	80	0 to 4000	The space below the cells.
Left Margin	80	0 to 4000	The space left of the cells.

The columns and rows start at 4 and 3. Set them in the top bar.