4 years, 11 months ago DT Team !!!
We have checked the Featured Image section in our local and we do not have any issues in it. It is working perfectly. Please try disabling all the external plugins other than the theme recommended plugins and have a look. If you still have any issues, mail your WordPress and FTP Login Credentials through the right bottom form @ http://themeforest.net/user/designthemes so that we will check the issue.