first you need some varables, "Time" and "Day" have both be a number and start at zero Also every time you compleat a event that will remove time left simply add X points to "Time". You will want to add up so when Time=X becomes greater than 24 reset the varable "Time" to 0 and add 1 to "Day". And consider 0 to be 12PM so you can start with Time=12.
To change day/night as you progress Have a condition that when Time>=19 & Time <=6 change you backround to night and another that when Time >=6 & Time <=19 it turns to day.
Also have conditions for when Day=0,1,2 etc to mark your progress and do unique actions. Actually you can use the command Groups, right click in the event sheet. And have things spefific to Monday be in the Monday group, Tuesday in a Tusday group etc. Groups can be turned on and off so one could have only certen things happen when a group is active.
To have a sleep feature simply set the varable Time=When ever you get up and add 1 to Day
I hope that helps get you started at least.