Think I have fixed the leak today. Thank you to all who responded!
I am providing some info which may help others.
Here is what the problem was. There is a rubber hose connecting the drain in the front corner of the sunroof "channel" to a metal tube which runs down the windshield pillar. It was disconnected from the drain. Now how could that happen? There should not be any way that it can, really.
This was hard to find as the water was leaking in the area of the electronics at the driver footwell. In order to find it I had to repeatedly disassemble, pour water and check for leaks until I found the source. By the time I was done I had looked behind the fender liner, behind the electronics in the footwell, all along the windshield pillar and finally above the headliner near the drain. Great fun!
There is another potential leaking problem which I came across. Behind the electronics in the footwell there is yet another rubber hose which connects to the metal tube in the windshield pillar and directs the water out of that cavity into one which drains to the outside (behind the jacking point). The hose is barely long enough to reach. I had to keep it place in it's hole with packing foam.