I think I already talked about this "bug" previously
so I am not supposed to argue it. When you install miniBB by default it should not provide this layout - the layout should remain with the classical view, i.e. forum listing is following first, recent discussions last. At least this is fixed in the recent version of miniBB 2.2. If you start experimenting with options you must know what you are doing.
I understood about the layout and it's up to you to implement it. It doesn't affect the default version. However what really looks strange on your forums that supertitles has no meaning. You have just 2 forums - and there are 2 supertitles. Supertitles may be created to separate specific forum sections united by the same theme. In your case they are not needed at all.
However please do not discuss this anymore... I hope I answered your first question; others are subject of your own implementation.