Thank you for your reply. I have been fiddling round, and have got a major improvement.
The mouse warping seems to work fine. I think it may have something to do with the fact I was using it on a second display using ‘extend these displays’, although I don’t know why it should have exhibited the behaviour it did. Now I am using it on the laptop (AlienWare) native display and it seems to work in Unity, all the demos work and the ‘rotate cube’ tutorial also works. However, the cube only rotates when you look at a position a few inches above and to the left of the cube. I checked the calibration, and even on the EyePosition demo, the calibration seems fine. But on the rotate cube tutorial scene I have created, and all the other demo scenes, the eye gaze position is completely out of whack.
I’ll try a few more things, but then maybe I will try a different eye-tracking solution.