Hi @JoostWesseling, we're in a slight amount of disarray with respect to Xively (see this blog post), and airqualityegg.com is pretty tightly coupled to Xively at the moment. Your data is still getting published to OpenSensors.io though, and you can download the data in CSV format using this web-based tool we've been working on.
Also we've been working on improved Wi-Fi hardware and if you've been having been unhappy with Wi-Fi performance, we would like to offer you a "hardware refresh" opportunity. If you're interested in that please email us at support AT wickeddevice DOT com.