I haven't been banned, using it for -Counts on fingers and toes- around 20months (Almost 2 years) so far? :]
It's not new, it was the original method, which was then turned into the DXWnd program method which was preferred by hackers because it stopped GameGuard from mass-sending all detections it made when you close it right before it opens "ad."
Anyway, if you get caught, yes you can be banned.
Chances of you getting caught : Slim to none.
Also, NxJoeW (I don't see him as a NexonUSA employee but many do), said somewhere that you will be banned, but also that GG won't consider it a problem.
As for the dll, it's a library, therefore not referenced in RAM (From what I know anyhow), so this shouldn't be detected at all. (Mainly why I use it)
Oh and don't use mini.dll you don't need it, just put GR2D_DX8.dll in there, replacing it with the old one.