>The first click *did* do something -- it changed the focus to the grid cell. The button can't react to click because the click event doesn't pass through the cell (i.e. the grid cell must get focus first before any events get passed to the contained objects).

This statement is not universally true.

For example: I have another grid on another form that doesn't have this problem. In this other grid there is only 1 column. In each row there is a container. In each container there are textboxes, labels, and buttons. These buttons DO NOT require dbl-click. They respond on the first click. I've tried and tried to isolate why one works properly and one doesn't to no avail.