Many people have hidden the info window successfully. I now get a recordset error when viewing the page, so it appears you may be in the middle of something else.
It could be a permissions problem. Our extension creates a cache file with the geocoded results to prevent a limitation in the number of data points, and if the file is not created properly because of permissions it may cause other errors. Can you find the cache xml file and see if it is being created and populated? That might be the issue.
Having a url where I could view the problem would help me debug it.