It is pretty easy to add in to GroveWeatherPi. If you want to wait until June, we will be releasing a AirQuality Expander Kit for the GroveWeatherPi. The hardware is identical with the OurWeather AirQuality Extender kIt, so you can get one of those. The software is not hard and is on our list.
I've been trying to get all this together for several months now, so it'l be great to finally get it out on a pole and producing data! Yay! Please let me know what steps are needed in order to add in the AirQuality Extender kit, I assume I won't need the mux since I already have one?
We are just starting our redesign of GWP to support a couple of difference sensors and some low power considerations. If you want to see how we plan to do it, read the postings on Project Curacao2 and how we build it into that project on www.switchdoc.com