Hi Arnold,
Sorry for the delayed reply on this. I wanted to have a think about the best answer, and then time flashed by...
Anyway, the short answer to your question is that, in order to use PyMata with the Pi Co-op, a specific Firmata sketch must be loaded on the Pi Co-op. You can either load this sketch manually using the Arduinio IDE, or it will be automatically loaded for you when the Python PyMata library starts up. Essentially the PyMata library starts up and tries to communicate with the Firmata sketch using serial. If it can't communicate then it automatically uploads the sketch using the
Ino library.
So, if you want to use PyMata, you have to either use the Firmata sketch, or you can modify it to do the extra things you want.
What special events exactly do you want to monitor? Can you give some examples please? I think that you might be able to do a lot of what you want just using Python. The main thing you can't do easily is respond to pin interrupts (so respond immediately if a pin on the Pi Co-op goes from high to low).
Regards
Alan