The MultiColumnComboBox tab of the Cell Type dialog in the Spread Designer contains the settings for customizing the multiple-column combo box cell type that can be applied to cells.
For information on the individual properties, refer to the MultiColumnComboBoxCellType class in the Assembly Reference.
For information on the Background tab for customizing the background of this cell type, refer to Background Tab.
For more information on the multi-column combo cell type, refer to Setting a Multiple-Column Combo Box Cell in the Developer’s Guide.