What do these temperature data listed in the EASA Type Certificate Data Sheet mean?
The Maximum Permissible Indicated Turbine Temperature (ITT) is the maximal operating temperature that you can accept without reducing power or shutting down the engine. This temperature is taken at the turbine entry and the limit is there to ensure good cycle endurance of the turbine blade. Higher temperatures and you will have increased fatigue degradation due to reduced mechanical properties. Now your question is why are there 3 different ones:
The maximum continuous is the maximal operating temperature of the engine for infinite life cycle endurance. At that temperature the engine turbine should not wear for the whole life of the engine. But in certain condition it might happen that the temperature exceed this value and in specific cases it was taken into account during the design.
The take-off temperature is what is going to dictate your power input, obviously you want 100%, but high AOA, slow relative speed means that your engine is not max performing and as you are applying full power, you might end up with a richer air-fuel ration than normal condition and see a temperature above your maximum continuous quite often. But the 5 first minutes of the flight at takeoff are critical so reducing power would be not good for safety, thus you allow for slightly higher temps, for a short amount of time.
And for the Maximum starting temp is the absolute limit you should never exceed. During startup the airflow inside the combustion chamber is not perfectly installed and it might happen that the combustion flame come closer to the turbine in addition to the richer air-fuel ratio than in normal condition, thus seeing increased temperature. But this should not extend for more than a few seconds or you'll have to shut down the engine.
Concerning the sea level static thrust this is the maximum output you can ask from the engine and only up to the max temperature indicated. Above that temperature you would see a decrease in performances to prevent exceeding ITT. This would then resume in reduced takeoff performances.