Das ist Ressourcen Fressend 
Mach es einfach so wie ich immer:
Mit nem Timestamp
der nimmt die zeit in Sekunden
Beispiel:
new LastDuty = GetPVarInt(playerid, "LastHolzDuty");
if ( Get_Time()-LastDuty < 600 )
{
new NextFarmIn = floatround(((600-(Get_Time()-LastDuty))/60));
SendInfoMsg(playerid, sprintf("Du kannst erst in %i Minuten (%i Sekunden) wieder als Holzfäller arbeiten!",NextFarmIn, 600-(Get_Time()-LastDuty)));
return 1;
}
SetPVarInt(playerid, "LastHolzDuty", Get_Time());
Dazu noch Get_Time von FoxBan 
stock Get_Time()
{
new fxban_int_hour,fxban_int_minute,fxban_int_second,fxban_int_year,fxban_int_month,fxban_int_day;
gettime(fxban_int_hour, fxban_int_minute, fxban_int_second);
getdate(fxban_int_year, fxban_int_month, fxban_int_day);
return FB_mktime(fxban_int_hour,fxban_int_minute,fxban_int_second,fxban_int_day,fxban_int_month,fxban_int_year);
}
stock FB_mktime(hour1,minute1,second1,day1,month1,year1) {
new timestamp2;
timestamp2 = second1 + (minute1 * 60) + (hour1 * 3600);
new days_of_month[12];
if ( ((year1 % 4 == 0) && (year1 % 100 != 0)) || (year1 % 400 == 0) ) { days_of_month = {31,29,31,30,31,30,31,31,30,31,30,31}; }
else { days_of_month = {31,28,31,30,31,30,31,31,30,31,30,31}; }
new days_this_year = 0; days_this_year = day1;
if(month1 > 1) {
for(new i=0; i<month1-1;i++) {
days_this_year += days_of_month[i];
}
}
timestamp2 += days_this_year * 86400;
for(new j=1970;j<year1;j++) {
timestamp2 += 31536000;
if ( ((year1 % 4 == 0) && (year1 % 100 != 0)) || (year1 % 400 == 0) ) timestamp2 += 86400;
}
return timestamp2;
}
Gruß