Ford Galaxy/VW Sharan Key Programming Procedure FAIL

This is how 2-button remote keys are programmed for a Ford Galaxy, a VW Sharan and a SEAT Alhambra (all basically the same car). In my case, it fails. I don't know why. The car is going into programming mode, hence the solid red LED in the door, and the key is flashing like it should do to say that's in programming mode too, but the two don't seem to be on talking terms. Either the key isn't actually talking or the car isn't really listening. Anybody else encountered this issue before?