I have an Office2007 style ExplorerBar. I have a group with about 7 items in it. There doesn't seem to be an option to not show any images with the text. Ideally, I would like to only show an image for certain items. Currently if I don't set an image, the default "no image" icon still displays.
The UltraExplorerBarItemSettings class exposes several properties that are applicable here. The UseDefaultImage and ReserveImageSpace determine whether the default image is displayed and if not, whether space is reserved in which to display an image. The latter can be used to make text for all items line up even when some items have no image. The AppearancesSmall/AppearancesLarge properties return a bunch of appearance objects, on which the Image property can be set to specify the image to be displayed.
The control and each group exposes an 'ItemSettings' property which returns an instance of this class, and each item exposes one via the 'Settings' property. To change the image for one particular item, use the UltraExplorerBarItem.Settings property.