The door seals on the drivers door have now been fixed (I hope).
Removed the door card to find this little lot:
The culprit was the dreaded seal from the groove the runs around the ancillaries carrier, which had rotted in places.
After the application of 8mmx8mm butyl tape and some generous pouring of water down the window pane to test, the
problem seems to be fixed. Its now draining from the drain holes beneath the door, instead of into my car. I'm sure mother nature will put it to the ultimate test sometime this evening.