The Ingame clock stopping or losing dawn to day and dusk to night transitions are the first signs of server wide lag. While it occurs on many PWs, if you're really picky, detailed, bah .. just outright anal in your building and scripting, your module could never suffer from it. For my own module, I had to do alot of things in conjunction to get the clock to be reliable. Palletes are trimmed, scripts optomized, area sizes decreased in many instances, building details like setting most objects to plot and static along with limiting placeables that interfere with pathfinding in hostile areas and tons more. By being almost obsessive in how I build nowadays, my module clock rarely if ever falters now (960 areas currently). Before I became obsessed with efficiency, my module clock would stop (only 250 or so areas then) quite often.
I do have a clock forcing script if needed though. I used it in my module's OnHeartBeat event until around a year and a half ago.
void main()
{
int iHour = GetTimeHour ();
int iMinute = GetTimeMinute ();
int iSecond = GetTimeSecond ();
int iMillisecond = GetTimeMillisecond();
SetTime(iHour, iMinute, iSecond, iMillisecond);
}