I did the migration from Geomajas 1.7.0 to 1.10.0-SNAPSHOT and the view of the features in a map is not working correctly. With the old version i hadn't got any problems to use diferent icons to represent features, even using a diferent icon with the selected one.
With the new version it doesn't work properly. They show me the same icon for every feature despite of the formula, and the property "selectionHref" is not working at all. Have you made any changes in that part of the app? I looked the code and configuration files of the Geomajas showcase to sure myself and i didn't found anything diferent.