Ok so i got the clock apart, (with some damage to the front black ring). Cleaned the little point things. Dropped a tiny screw but amazingly found it again. Hooked up a spare battery. Got it make a little click so assumed it was winding up the spring. But it would only go for a few turns of the wheels before it stopped. So as Mr Hobby said I assumed it was a bit gummy. Blew it out and sprayed a tiny bit of Inox, (not WD40), around the bearings and gears. Pressed start again and it kept going this time. So I'll leave it to run for a while and see if it keeps going. Don't know what watchmakers use for lubrication -if anything - probably whale oil or something. Notice the American chap in the video recommends only turning the clock on when the car is actually being used to avoid the points burning out from continuous use. Can't be bothered with that. If it works when it goes back in the car I'll be happy.
You can buy specialist clock oil quite cheaply. Use it very sparingly. If the mechanism is a bit gummy then the spring doesn't unwind sufficiently before the clock stops for the points to make and wind it up again.