First off, the thing is free. So really, theres no need to really put a thread here.
Secondly, its a .PSD not an image set or something. Its an LP, or Layer Play, .PSD, meaning you open it in photoshop or SAI and mess around with the layers to make your own set. All of the default stuff, the ones that pwny posted at the time of release, are already on like, derpibooru and such.