I am glad that you managed to find a solution to your problem. The CellFormatting is the appropriate event to customize the style of the cells. Casting the CellElement to the appropriate cell type is the right way to ensure that the desired cell will be customized.
Note, since RadGridView uses UI virtualization, its cell elements are created only for currently visible cells and are being reused during operations like scrolling, filtering. In order to prevent applying the formatting to other columns' cell elements, all customization should be reset for the rest of the cell elements. Do not forget to provide an else clause in the CellFormatting event and reset the visual changes. More information is available here: https://docs.telerik.com/devtools/winforms/controls/gridview/cells/formatting-cells.
I hope this information helps. Should you have other question I will be glad to help.
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