Sorry @RMAK, but the method you already found, looking at the results in Results Viewer, is the only simple way to view the Radiance simulation data with OpenStudio. As @nfonner mentioned, there is no architectural context with this data; you are merely seeing the shape of the individual illuminance map, and you can only view them one at a time.
One workaround for this in the short term is to make a single illuminance map that covers an entire floor (as best you can with a rectangular map, anyway), set your interior thermal zone boundaries to "air wall" constructions (so the daylight can pass from perimeter space(s) to interior ones), and add any interior geometry with interior surface partition groups and objects. The resulting illuminance map will show the spatial distribution of the daylight and will show the effect of any interior walls or other objects. If you have a high enough resolution illuminance map grid, and good detail of the interior space, you get a very clear picture of how the building is admitting daylight and what's happening to it inside the building. Maybe not persentation quality, but useful for design work.
Yet another thing we are working on adding to OpenStudio is an improved data format and some plotting routines so that you can do better building-wide data visualizations in a dynamic way.
