I would not use InstallOnTimerScript for this. If hosted from FileMaker Server, you can use a server scheduled script that adds one such record every day.
If you do not host the file with server, I'd use file options to set a script to run each time the file is opened. The script can check to see if a record with today's date exists and create one if one is not found. This script can also be set to create previous days as well as today's to "catch up" in cases where the file has not been opened for a day or more. (And this is not a bad approach for a server scheduled script either as there are circumstances that might keep a schedule from performing a script on a given day.)
Thank alot Phil,
What sort of script do I have to write so the dates are created upon file open, can you please tell.
Go to Layout [DatesTableLayout]
Enter FInd mode  --> clear the pause check box
Set FIeld [YourDatesTable::Date ; Get ( currentDate ) ]
Set error capture [on]
Perform Find 
IF [Not Get ( FoundCOunt ) // no record with today's date was found ]
Show All Records
Sort Records [Restore ; no dialog ] ---> sort by date in ascending order
Go to Record/Request/Page [Last ]
Set Variable [$Date ; value: YourDatesTable::Date ]---> set variable to date of most recent date in table
Set Variable [$Date ; Value: $Date + 1 ]
Exit Loop if [ $Date > Get ( CurrentDate ) ]
Set Field [ YourDatesTable::Date ; $Date ]
Go to Layout [//specify the layout you want the user to see when they first open the file here ]
A robot file can also be scheduled to be opened and run this script once a day via an OS based task scheduling utility if you don't want this to run every time the file is opened.