Master Greg has been working on decoding NBA 2K15 files. It´s not an easy task. NBA 2K15 is using textures having dx10 headers ( for DirectX 11 ) and currently there is no tool to preview them. These seem like normal dds files, they are packed together with their appropriate dds headers, but they are a bit mixed. They need some kind of conversion which Greg managed to find out !
Screenshots Gallery
He is developing an archive explorer for NBA 2K15 but it will take time. As it will take time to understand how to import files back to game or even mod this game properly. But this is a big step.