Hi Daniel,
I’m sorry but this is a forum for developers and the EyeX really isn’t intended for people with disabilities. Instead I’d recommend that you check out what Tobii Dynavox has to offer, this is what a colleague from TD said:
We think the best solution for your father is our package with an eye tracker and a full eye controlled windows access software, the PCEye. With this package you can completely replace a mouse and a keyboard with your eyes (video).
If your father only want to be able to click we are about to launch another product package during next week. Check out this link end of next week. With that product you can only perform mouse left clicks.