ECW (other raster formats as well) images plot black from the Layout Window.
GeoMedia currently has a problem plotting 4 band ECW (and other 4 band format) images (CR-Defect 1-ANAB3S). This is a common format, with the 4 bands being visible blue, visible green, visible red and near infrared parts of the spectrum. Other 4 band image formats also have this problem.
The workaround is to convert the 4 band ECW to another format, usually just 3 bands; RGB TIFF format would work well. This conversion can be done by Image Station Raster Utilities, downloadable from this website, or by many third party tools.