Line pressure is fine, it is in-spec.
40psi control pressure is too low, it should be 50-54 psi when the engine is fully warmed up. Control pressure is inversely proportional to mixture richness, so a too-low control pressure will mean a too-rich mixture (assuming everything else is in-spec).
The CPR, when the car is running, is heated, that's what the electrical connector for it does. The testing procedure for the CPR is to supply 12V to it for 5 minutes and then measure the pressure, but you can also just run the car for 5 minutes and then take the warm reading. The ambient temp reading is just for determining expected cold start pressure based on ambient temp.
Testing the injectors is a good next step. If they produce a fan at all loads they are fine, and you also want to compare them to each other and verify they dispense the same amount of fuel.
The fact that you have a CPR that should be causing a rich mixture, but are observing symptoms of a lean mixture, says to me you have some basic issue with your fuel delivery. Injectors could explain it but they seem to be worse at lower RPM and then perform better at higher RPM when they have more pressure behind them, so maybe it is debris in the system upstream of them too.
