Thanks to Godra, this topic mentions the problem:
http://advancedhmi.com/forum/index.php?PHPSESSID=da5d0226a4afc5ebb371489a3adc4ac5&topic=377.0I have 20 basic labels assigned to counters in the PLC5 controller (counter 0 thru 20), and when I add the 21 counter, that counter blinks. However, if I add an object that is assigned to something not within the "20" word range that basic label does not blink. I do not appear to be getting any exception errors, but I can stop the blinking by assigning another driver to those basic labels.