FpSpread1.Sheets[0].Cells[1, 1, 3, 3].Tag = "This is the tag that describes the value.";
FpSpread1.Sheets[0].Cells[1, 1, 3, 3].Value = "Value Here";
FpSpread1.Sheets(0).Cells(1, 1, 3, 3).Tag = "This is the tag that describes the value."
FpSpread1.Sheets(0).Cells(1, 1, 3, 3).Value = "Value Here"