Sorry to hear of your problems, I know this won't help any but my daughter bought an ex Police Astra. They rip the stereo's out to fit their computers. The problem is only the original stereo will work in that particular car, unless the stereo is "divorced" from the car. A new stereo has to be "married" to the cars security system.
Most people selling Vauxhall stereo's on
haven't done this so will not work in any other vehicle. This may be the case with Renault stereo's as well. Perhaps you also need the tuner and amp plus possibly the display screen.
If you get things to work, keep others informed.