I do this by making the top object a different size in the design mode and then resize it to the full size in the form init, or make it visible when I need it. This works for me when I have a normal form and I want to pup up a full form size grid. In the design mode I have the grid very small and out of the way, I can get reference to it at any time in dessign mode just by clicking. And I don't really care where I leave it. In this case, the grid is not visible, but when I click the button to open the grid, It becomes visible and resizes to the proper size. And I play tricks if the normal form is resized anyway.

HTH