We don’t have an official support for Ren’Py or Python, but it is possible to call into FMOD from Python using ctypes.
I have written up a small example of calling into FMOD from Python here:
http://www.fmod.org/questions/question/how-to-use-fmod-from-a-python-script
In theory it should be possible to do something similar from Ren’Py.