I have followed the instructions in http://clonedeploy.org/v1-3-0-patches/ multiple times for upgrading 1.3.0 to 1.3.1 and 1.3.0 to 1.3.5.
Each time I performed the upgrade, no matter which version I upgraded to, I could no longer deploy or upload images. Clients would return Error 500: Unable to download scripts.
After finally finding this thread (https://forum.clonedeploy.org/721-response-code-500) and running the chown command as follows on CentOS 7, the issue has been resolved.
chown -R apache:cdsharewriters /tftpboot/ /cd_dp/ /var/www/html/clonedeploy/