About pressing in the options menu: yes, I was thinking the same. The menu is heavily based on the one from the first Gran Turismo and pressing A did the thing you described. Not sure about B and Y, but I'll see what I can do.
Yeah, it indeed works the same way. If you ever unlock the motorcycle or F1 car: you have to hold the button. 😉
Yes, that would be a nice addition to the simulation! I believe I already have an ambient temperature that determines how fast the engine cools, but it's set to 20°C. Maybe I can make it a bit more dynamic, depending on the conditions.