>I need to make sure all the instances of my app are shut down just before midnight for backup purposes. How can't seem to get Time() > "11:30:00" To work.

two options:
IF HOUR(DATETIME()) > 23 AND MINUTE(DATETIME()) > 30
...
ENDIF

IF SECONDS() > 21,5 * 60 * 60
....
ENDIF

You'll have to set this up in a timer control.

Be warned that timers don't word when dialog boxes are active.