One "naive" way to detect blinks is to monitor the datastream for momentarily lost tracking which could indicate a blink event. I've made a little application called GazePlotWPF that draws the x/y/pupilsize for each eye and flashes the background when a potential blink occurred. It's not 100% accurate but could be enough to get some ideas going.
Source code is
available on Github. I've also made a
pre-compiled binary for your delight.
Proper eyelid closure and accurate blink detection is still on the roadmap, ETA unknown.