Thanks for testing, guys! You can actually pop into our http://www.cotonti.com/chat to share some messages.
It is supposed that Genoa to Siena upgrade should work normally now.
Dave, those "Wrong URL" messages after upgrade usually mean that some of your third-party plugins or system/functions.custom.php contains
defined('SED_CODE') or die('Wrong URL');
while this statement is not legal anymore. Please check that.