About the 1:1 Rising Rate Ratio
This is the ratio between boost pressure and fuel pressure increase. A 1:1 ratio means that for every 1 PSI increase in boost pressure, fuel pressure will also increase by 1 PSI to ensure that the pressure differential between the inlet and outlet of the injector is constant. Effectively, injectors are solenoid valves which open and close when power is applied to them.
If fuel pressure is too high, the injector solenoid will not have enough energy to open the valve fully causing the engine to starve of fuel. It is essential to maintain a constant pressure differential between the inlet and outlet of the injector and hence why a 1:1 ratio is ideal.