How did you initialize the images for the GoIconicNodes in your GoPalette? You should have provided a Name of a resource or disk file, or an Index into an ImageList, in your call to GoIconicNode.Initialize.
If so, and if you can use a single source of images, then the easiest solution is to set GoImage.DefaultResourceManager or GoImage.DefaultImageList. Alternatively you can set GoView.ImageList for each view.
Most generally, you can implement a GoView.ExternalObjectsDropped event handler on your view to make sure each dropped object is initialized the way you want. In this case, it's making sure the GoIconicNode.Image has the properties you want. But I don't think you will need to do that for handling regular drag-and-drops from a GoPalette.