Hi,
I want to control crazyflie from openFrameworks, so I developed add-on.
https://github.com/Saqoosha/ofxCrazyflie
Currently, this is super alpha version and it has some bugs, but it works almost same as cfclient.
I don't have any windows development skills, so it only works on Mac now. I think it's not difficult to port to windows, because this add-on was built on top of libusb.
I'll add some examples later which controls copter by gamepad (using ofxGamepad).