I figured out a way to do this, but you'll have to judge for yourself if it is acceptable.
A contrasting background color that goes away when the time limit expires would be simpler to set up and less likely to engender an unacceptable performance hit.
Put a conditional format expression on your field with this expression:
Set a contrasting fill color for this conditional format.
Write this Script, called "Flash Text":
Set Variable [$$Flash ; value: Not $$Flash ]
Write a second script:
Install On Timer [Flash Text ; 1 ]
Write a third script:
Install On Timer 
Set Variable [$$Flash ; False ]
Run the second script to start the field flashing on a 1 second interval. Run the third script to stop the flashing.
To make this work for 72 hours, you'll need to store an expiry Time Stamp in a field the flash script can check this field and when Get ( CurrentTimeStamp ) is greater than the stored value, it can use steps similar to the third script to disable the Intalled timer.
I will try this.
Kinda sounds confusing LOL.
I will let you know if this works or if i need more help
yes i do not understand this. More help on this would be great
Tell me where this goes off the rails for you and I'll explain in more detail starting from that point.
Can you set up a demo file and use the three scripts to get the text to "flash"? (Run the second script to start the flashing and run the third script to stop the flashing.)
I cant even do that. I dont even know were to start.
- Define a text field, FlashText and put it on your layout if it isn't added automatically.
- Right click this field while in layout mode and select Conditional Format from the menu that pops up.
- Click the Add button
- Select Formula instead of Value in the drop down.
- Type in this text as the conditional format expression:
- Select a bright pastel fill color such as yellow.
- Click Ok to dismiss the conditional format dialog.
- Enter browse mode and type some text into the field.
- Define the three scripts, run the second script to start the flashing. Run the third script to stop it.
Try following those steps and let me know where you get stuck.
1st part is done
1st script keeps telling me something is missing?
By the way text feild is called (Whats New) If this helps
I see a typo in that script:
Set Variable [$$Flash ; Value: Not $$Flash ]
take out that extra "e" that snuck in when I typed the script.
i copied pasted exact and it still tells me im missing an operator?
in set variable there are 3 feilds
Am I doing something wrong?
All you sould see in the value box is: Not $$Flash
Figured it out now ho0w do i use that 1st script
It's run by a "timer" the second script creates when you run it. That's what the install On timer step does.
ok all scripts are done
-and so is the conditional formation in my Whats New Feild.
So what do i do now?
Run the second script and watch it flash.
The second script sets up a "timer" that runs the first script on a 1 second interval. Thus, every second, the conditional format's expression re-evaluates bouncing back and forth between True and False and thus the fill color in the field appears and disappears. You could specify a Text size of 500 if you want the text to appear and disappear instead.
Run the last script to stop the flashing. When you perform a script with the Install On Timer Step and don't specify a script or interval, this step takes down the timer created when you ran the second script.