>Is there a way to detect mouse click outside a grid whwn I am in a for example column1 of a grid through valid (or lostfocus) method of column cell?

If I understand the question correctly, you can use BindEvent() to assign mouseclick to column cell if you add columns to the grid programmatically. To code behind Valid and Lostfocus of text boxes within grid, this is most easily done by subclassing the controls and adding them to the grid programmatically.

HTH,