The Windowizer plugin (version 3) created by Rick Wilson on Smustard.com is a simple tool to create windows for your SketchUp model. It gives you many options such as trim colors, glass styles and arrangements.
Using the plugin is simple but not really that intuitive. You need to make sure that you select a single face and know that the face will become the window area. Once you select the face then right click (on windows) and select the Windowizer tool. Then you have a set of options to select from, allowing you to set the amount of rows and columns, frame and mullion sizes, insets, and glass and frame colors/textures. Note that if you cannot see the drop out menu, then your face needs to be exploded further. The tool is very simple and works well. Though it would be helpful if there was a toolbar also available for it.
Overall, the Windowizer plugin (version 3) created by Rick Wilson is a simple but yet effective tool to create windows, especially store front ones. At the time of this review this plugin is free and is available at Smustard.com. I give this plugin 4 out 5 stars.