I have sent this same question to Renault Sport and this has been the answer:
Good Morning Dear XXXXXX,
To follow up on your question. It is true that you can rely on the parameters indicated by the RS Monitor.
In addition, the engine and the gearbox have thermal protections which will be activated in the event of high temperatures.
But before having a warning light on the dashboard, you will have a feeling of lack of power at the level of the engine. This is the first sign that a temperature is starting to rise.
If I can give you any advice, especially in high heat. The ideal is to vary the laps between sporty driving and cooling laps. Example: 3 full turns and 2 cooling towers.
The cooling tower is very important, not only for the engine and gearbox, but also for the brakes.
Last thing also, it is strongly advised to stay on the original fluids, whether for the engine / gearbox and brake. If the heat conditions are important and you do a lot of circuiting, then more frequent fluid replacement would be perfect.
I hope I was able to answer your questions.
Have a nice day