Support for the PHP Echo shortcut is apparently not supported in the server at this time. Not sure if this is a new thing that was added to the pages header or if support for the echo shortcut was removed, but to keep '?> from showing up at the top of the main page the line:
<?= '<?xml version="1.0" encoding="utf-8"?>' ?>
needs to be changed to:
<?php echo '<?xml version="1.0" encoding="utf-8"?>'; ?>
either that or just:
<?xml version="1.0" encoding="utf-8"?>
and avoid the PHP all together....
Either way should work. I just thought I would point this out.