You can implement polygons using the region functionality which is included in the out of the box google maps widget. You just need to create an infotable that contains a param of type "location". Each lat,long location point that you define in your infotable becomes a point in your polygon. You bind this infotable to the "RegionLocation" parameter in the google maps widget.
To add a heatmap, you will need to customize the google maps widget to enable that functionality. You'll need to add functions in the widget javascript to display the heatmap. You'll also probably need a new data binding property for the heatmap data. If you study the ide and runtime javascript code, you should easily be able to figure out how to add all the extra services and data binds.
