I get wind noise ( Like a flutter) and a slight leak in very heavy rain when driving at speed from the drivers door. Any ideas......

Buy a 2 inch wide roll of masking tape, and tape up all gaps around the door and window. Scramble into drivers seat from passenger side and drive at speed. If noise has gone, remove the masking tape a gap at a time until the noise restarts. There's your problem gap!

Try adjusting the striker plate on the B pillar inwards! We had a similar noise and I tweaked these which got rid of it. Unfortunatley the door is now slightly less "flush" than it was before but it's hardly noticeable.

Cheers