No, as he's confirmed it was indeed water in the plenum chamber in front of the windscreen and that seems to be caused when anyone regularly parks their car under or near trees. The leaves simply drop into the chamber and eventually rot down, thereby blocking the drain. A fine mesh on the grille at the base of the windscreen would stop this, yet still allow the heater to draw air satisfactorily.Isn't the problem 994runner describing different than the one described in the PDF file? There seems to be two very different water problems reported in this thread. Water inside the rocker panels, and water in front of the firewall, far down under the windshield as the PDF file demonstrates where the water drains out from.
Yes, there are two totally different problems.
And, no: no one yet has come up with an answer about the water in the door sills . . .