To Customize a Standard Product Icon

Follow the procedure To import an icon from an MDL resource file.
In the Current File Icons list box, select the icon you want to customize.
In the Icon Properties pane, select icon size that you want to customize.
Right-click the icon and select Export to Bmp or Export to Png.
The exported file is placed in the same folder as the configured DGN library file. The icon's width and height information is added to the file name.
Open the exported file in image editing software and make the desired changes.
Follow the procedure to import an icon from a Bitmap file.
Note: This procedure can be used for any imported icon.