Hello Andy and Javier,
wondering how this is going? Is there a reply to Andy's question about the configuration of the control?
reading into previous msgs, Andy, you have a daughter that you are wanting to use eye-gaze for her to access computer? My interest is also accessibility and augmentative/alternative communication.
I don't know that it is a long term solution but check out Camera Mouse
http://www.cameramouse.org/Note: this requires Windows platform.
I found it it to be unexpectedly accurate - and it is a mouse substitute. You can either "click" by a dwell setting or you can keep this off and click via a single switch that is functioning appropriately (for users who might benefit from exercising switching control over clicking.
I am hopeful that down the line, someone will develop the software for the Tracker that would be generic in this fashion. To my mind, that would be watershed for Tracker functionality (are you listening, Eye Tribe?)