The Combo Box tab of the Cell Type dialog in the Spread Designer contains the settings for customizing the button cell type that can be applied to cells.
For information on the individual properties, refer to the ComboBoxCellType 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 combo cell type, refer to Setting a Combo Box Cell in the Developer’s Guide.