drag & drop in datagrid

1-if i try to drag and drop a row in a datagrid after make changes in this row and save dataset is unabled to save .
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2-when i make change in a row in datagrid and try to save this change through toolbar button it is unable to save ,although it saves if this code is in a button.
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3-how can i change the format of datagrid cell
(change the format of the cell to display time as days:hours:Minutes).
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Look here, lots of info.
http://www.syncfusion.com/FAQ/WinForms/default.asp#44