OK, I have cleaned the code and isolated the problem: attached the sketch with the problem visible.
It is possible to load in Arduido and see the debug light that must be on but is off.
The problem is created by the Arrays managed in the function SetTime.
if you try to move the declaration part
//Timers
unsigned long LastTimeLoop;
int Ore[MaxTimers];
int Minuti[MaxTimers];
int Secondi[MaxTimers];
int Millisecondi[MaxTimers];
int TimerName[MaxTimers];
int TimerEnabled[MaxTimers];
at the end of the declaration seems to wotrk fine....
Thanks
TestCode.ino (18 KB)