My Keyboard was completely dead. Thanks to the info in this forum, and to two very skilled electrical engineers we managed to bring it back to life.
It turned out to be two things:
1) the FPGA's got de-programmed, so loading the codes solved 80% of the problem. The codes can be obtained by different ways discussed in the forum (copy from old device, get it by someone who has it, etc). After loading the codes 75% of the keyboard came back to life.
2) Then with the upper left side still not working, my super-skilled engineer colleague noted a broken leg in a part of the circuitry, soldering it did the trick. He also improved some other worn out solderings (as is recommended it some of the Repair Tactic pages)
You cannot imagine how happy I am, I feel like i got my life back. I was working with my Ipad using the Remote HD App, which is actually quite nice, but obviously not the Touchstream. I would have take me ages to get to speed, and maybe could have cause me some new RSI

Thanks so much for your support, thanks to the entire forum, and particularly Torben.
All the info for repairing the keyboards is here. But you need to be either an expert in FPGA and Circuitry, or having the right friends with the right tools

I will get them a nice bottle to attempt to represent my gratitude.
Long life to the Fingerworks TS LP!
Antonio
ps: I found the instructions cryptic at the beginning, but I then understood them. I will be happy to help anyone who is in the same position. Send me a message and we can chat on skype or similar.