The presentation of DK selected vectors (how these vectors are are highlighted on the map) is controlled using:

• GIS.SelectionColor to set the selection color, as long as the selection color is not white. (If white, then use instead GIS.SelectionPattern).
• ​GIS.SelectionPattern to set a bitmap fill for the selection. (Use only if GIS.SelectionColor = clWhite).
• GIS.SelectionTransparency to set the transparency level of the selection fill.
• GIS.SelectionWidth to set the width of the fill overlap gap (width of outline).