Help with tf2d

I was wondering if anyone could tell me exactly how to install and change themes for tf2d, I am completely lost. I have m2d customizer but none of the themes I download show up on the download manager. I don't know if I am installing them in the wrong place or not. I also was wondering if anyone could tell me how to get the album art to show up on audio manager. Any help would be greatly appreciated, I am pretty new to all of this and like I said am lost on most of it. Thanks