no injector signal

[Ivan141]

Yeah I would say check the ground wires as well... All 4 injectors not working can't be caused by faulty wires..that would be too big a coincidence, especially when I look at the neat state of things in your engine space.
As long as your using the ECU with the wiring loom that is supposed to come with it there should be no problem using wrong injectors (10 ohm difference would indeed still work).

Now I havent checked where the ground on the intake manifold goes to, but my guess is it's as close to the injectors as possible so they get the best signal quality (since the injectors cant be grounded directly to the cilinder head).

Bridge the diagnosis connector and have a look at that if you havent solved it already..
I assume you checked for fuel pressure at the return line?