No qualms with acquiring custom made minifigures and/or elements from sellers upfront stating such are in fact custom made and not trying to pass them off as official product (Brick Builders Pro and Firestar Toys come to mind). Now in the case with off brands guilty in outright copying what LEGO does but subpar quality like Lele, Bela, Decool, Enlighten, Sluban, and so on, the site's stance is quite the opposite.
I suppose the short answer would be if the item is made "by the fans for the fans" then it is alright.
There are plenty of already established topics to post in but nothing making any mandatory. They are simply there as easy to find, post, and discuss various "catch all" subjects. You can always start up a new thread to show off your latest works.