This sample illustrates the various options like floating, banner cells, covered cells, custom border cells and custom draw in grid cells to customize the cells in the Grid.

Floating Cells:

gridControl1.FloatCellsMode = GridFloatCellsMode.BeforeDisplayCalculation;

Cover ranges:

gridControl1.BanneredRanges.Add(GridRangeInfo.FromTlhw(rowIndex, colIndex, 8, colIndex + 1));