I have no idea what it means, but IT COUNTS!!!!! with the setup above! Now, what is the big problem with getting the same signal from the 339 output?As far as the display changing when the LDR is covered, I'd try removing the connection from the LDR circuit to the clock pin of 4553. Put a 10kΩ pull-up resistor on the clock pin and attach a N.O. momentary switch between the clock and ground. Now press the switch. Does the display change?