I’m pretty sure that’s not allowed, but you should send a ticket to Envato Support to be 100% sure.
I was having the same issue with few my items yesterday. Probably it’s a bug. If there is anyone else with the same problem please respond maybe it’s time for opening support ticket.
There was an official answer on this here: http://themeforest.net/forums/thread/new-feature-trending-and-recommendations/139162?page=18#1117278
I am unable to find that tutorial. Do you have a link?
Here it is: https://webdesign.tutsplus.com/courses/preparing-wordpress-themes-for-themeforest/lessons/overview It’s a ~45 minute course divided into several videos. You need to create an (free) account on that website in order to watch all the videos. Good luck!
P.S. That course is for WordPress development.