When I expand the row height, the combobox fills the row as in the attached picture, how can I force the combo box to remain the same size docked to the top?

I have tried the following

customCombo = new Infragistics.Win.UltraWinEditors.UltraComboEditor();

customCombo.Appearance.ImageVAlign = VAlign.Middle;

customCombo.AlwaysInEditMode = true;

customCombo.Dock = DockStyle.Top;

ultraGrid1.DisplayLayout.Bands[1].Columns["Custom RAG"].EditorControl = this.customCombo;

ultraGrid1.DisplayLayout.Bands[1].Columns["Custom RAG"].Style = Infragistics.Win.UltraWinGrid.ColumnStyle.DropDownValidate;

ultraGrid1.DisplayLayout.Bands[1].Columns["Custom RAG"].AutoSizeMode = ColumnAutoSizeMode.None;

ultraGrid1.DisplayLayout.Bands[1].Columns["Custom RAG"].CellMultiLine = DefaultableBoolean.False;

I have tried various Dock and anchor options, but no luck

Any suggestions