Easy =)
This is using SendMsg 3 "Its now 8pm"
In Envir/robot.txt add npc name (system, npc name, whatever) and script name.
System eightpm
In Envir/Robot_Def/robotmanage.txt, add script.
[@eightpm]
#ACT
SENDMSG 3 "Its now 8pm."
break
In Envir/robot_def/add scriptname text file eightpm.txt
inside put #AutoRun NPC RUNONDAY 20:00 @eightpm
Thats all.