I believe the ip2country lookup (auto detect your location) isnt working as it is disabled on most servers. There is a ticket to make this fail 'sliently' rather then return any notices or errors. Then The XML error is caused because of the notice being outputted. This will probably be part of the next release.
So I dont know the proper way to solve this but it looks to me like 3 things you could do
1) Work out way ip2county isnt working and enable it on your server (pssh too much work? and its not that useful)
2) Turn off your PHP notices - add error_reporting(E_ALL ^ E_NOTICE); to your mysite/_config.php file or set it in your PHP.ini file on your server setup (notices are some times useful so turning them off might hide some problems with your code)
3) Turn off Strict XML checking in your template so that it doesnt fail with a notice outputted - to do this remove the <? xml bit at the top of the file - themes/yourtheme/templates/Page.ss