This is how to prevent windows timeout or screen lock when it is out of your control.
There is a very old very simple program called delayer.
You put this program in your start folder nad set the options to run it in the shortcut which I will show you how to do.
First you need to download delayer and put it where you want to to run.
http://www.cottonwoodsw.com/dlyrsumm.html
You then want to set up a shortcut by right clicking the program and create shortcut.
Then rightclick the shortcut and select properties. You can then edit the shortcut.
The shortcut will determine how the program will work.
Here is my quick help file:
c:\tools\delayer "ping -n 1 yahoo.com" /D10 /R /M
options are "program you want to run"
/Dxxxx where xxxx = seconds up to 24 days
/R is to repeat
/M minimize the program you run
/H hide the icon for this program
I minimize the ping so I never see it run so it doesn't popup while I'm working. You can launch a text file with reminders or any other program.
Once the shortcut is created then save the shortcut in your startup folder.
If you don't keep the icon hidden you can open the delayer program and kill if needed.
I run the 32bit for windows 7, Vista, or XP.