Ensure the Alfa Ub ('constant' main power wire) lines up with the yellow wire to the CTSAR001.2.
There may be no ignition wire in the Alfa plug. In which case, you will need to connect the red wire from the CTSAR001.2 to a suitable 'switched' power wire, like the cigarette lighter power wire. This way, when you turn the ignition on, it triggers the CTSAR and radio on.
Use a multimeter to confirm the Ub wire (always +12V, thereabouts, regardless of ignition key position). And that the cig wire provides a switched supply (0V with key OFF, +12V with key ON). There might be an ignition wire in the Alfa plug, so you can also use the multimeter to check.
It would be helpful to see if there is a sticker on the original radio, similar to the photos I posted earlier. What does it look like?