需要帮助加载KML - 这是我的第一个Google Maps项目

This is my first Google Maps js project. I have used the Google Earth for some time. I have a page that has a drop list of KML URLs. Initially the map needs to center on a selected point. This works find. After the droplist selection it needs to load a KML file. The KML file I use is the same as used in Google Earth. I am viewing with chrome and see no errors.This is my first Google Maps js project. I have