My touchstream has just been repaired by friendly people with proper equipment. This would have been much, much harder without tips from pythagoras -- many thanks to him for the extensive repair hints!
To recap the story, I had a keyboard zapped by a static discharge, with 1/4 of the surface completely dead (half of the left half). It turned out that one of the Xilinx FPGAs needed replacement and reprogramming.
Again, many thanks to those from FingerWorks who care about us and post information!