I'm trying to use the suggested solution by the OP here:
and I've added the following to my CPT template file:
<?php wp_get_attachment_url(get_post_meta(get_the_ID(), '_ct_upload_568256198786e')); ?>
However I receive the following error:
Parse error: syntax error, unexpected '['
If I remove the array reference  the template loads but I get no output.