change the temperature ?

You need to find the theLevelInfo object and in it's properties go to temperatureCurveC, it'll look like this:
0 30 0.300000012 28 0.5 27 0.800000012 28 1 30

It's time, temp, time, temp, etc. 0 is midday, 0.5 is midnight, 1 is midday. Temp is in degrees Celsius. I hope I have this right but you need to specify 0 and 1 (they are the same time and therefore should be the same temp) and however many points you want in between.