Repro Steps:

1) Create a Page
2) Delete the Root Grid from the Page.
3) Click-and-Drag a Grid element from the Add Element panel to the Navigator.

Observe how the Grid is successfully added.

4) Delete the Grid added to the Navigator in Step 3)
5) Click-and-Drag a Grid element from the Add Element panel to the Stage.

Observe how the Grid is successfully added.

6) Delete the Grid added to the Stage in Step 5).
7) Select the Grid element from the Add Element panel.
8) With the Grid element still selected in the Add Element panel, Click-and-Drag on the Stage to 'trace' the shape of the Grid to be added.

Observe how it is not possible.

Expected Result: The ability to add an element to a blank page is consistent between all methods.