Hi, Thanks for your note. It's great to see you trying this.
When you have results it'd be great if you should share them for us to look at.
Unfortunately it's not feasible for us to provide FFT transforms for audio, for 2 main reasons: The size of an FFT for every frame of an entire song is pretty big, and to some extent it is reversible back to audio which is not a mess that we want to get involved in.
We're starting to make plans for computing and providing more detailed features (probably not FFT per frame, but a lot more detailed than the current summaries), and will hopefully finalise these plans in the next few months.