Hi - my 2004 FL1 TD4 drivers door electric window has sometimes been temperamental however it now will only open/close when the door is open - I suspect a dodgy wire but surely it would sometimes fail with the door open if there was something amiss wiring wise? Any ideas much appreciated please?

Sounds like a broken wire in the loom where it bends for the door. I haven't seen it before but FL1 leccy windows love to fail. It's their favourite mode.