Hey there, I didn't join NulledBB all too long ago actually, but all I wanted to do here is download some styles for my XenForo page. To be honest, I have no problem to register myself or to write 15 posts without any leeching. For many it would be helpful to see instantly when they come on a page, what they have to do to download Content.
Szenario: Person A searches for a free download of something NulledBB (also) provides, so he clicks on the Link and sees that one has to be a registered Member to download it ... he registers ... now he sees that he has to write 15 posts to be able to download something ... 1. he does as told and posts "meaningful posts" without leeching and then hopefully after doing these two steps, finally being able to download the Content, or 2. posting 15 leech posts which just spams the site and then downloads his stuff.
If people could determine before even registering themselves what other steps they had to do to get to their wanted download link, therefore be sure if its worth their time and maybe leave but at least not spam the Forums with leech posts.
So my suggestion would be to add a visible header when a new person joins the page to shortly and friendly introduce them to the sites concept and what steps need to be finished until one can download something.