Hi All
The problem has been solved and the cause of another strange one identified. First thing, a good piece of advice for anyone wanting to check wires behind the dashboard is apart from the side trim, remove the radio and ashtray. That helps a lot. The faulty connection was a brown wire that went to the lower left spade on the ammeter. It was only just touching, and the sparks (you could see them clearly) had completely toasted the insulation boot to the point where half of it was missing and almost all of it was charred black as opposed to clear plastic.
The reason that I could hear a relay clicking when I operated the windows, was that when the connection failed some power was going through the hazard light, and that was causing the hazard relay to click weakly and the hazard light to flicker.
Once the dash was back together I checked the indicators to make sure that the electronic flasher that I fitted still worked. Sure enough the drivers side was flashing at least twice as fast as it should have been. Plus it was flashing the front sidelight instead of the indicator. The flasher checked out OK so I gave up and moved on to the headlight pods where I have been getting them to operate better, and fitting a bar so that they move in tandem. I noticed that as the pod raised the drivers sidelight was coming on. And the rear indicator also. The drivers side headlamp was very dim. The passenger side headlamp was out, so I replaced it and ended up with one bright headlamp, one dim and both the single indicator and sidelight dimly illuminated. As soon as I saw that I thought "time for some wire wiggling, and sure enough there is a bad connection to the front drivers sidelight. After a wiggle it all works fine, including the indicators.
So the upshot is that I still have to get the windows working a bit faster but at least they work and I have learnt that one bad connection can cause a lot of things to go wrong!
Thanks again for the help
Berni