Here is a start to your vi. It shows you how to compare the 2 signals. We wont be able to help you much more as to writing more code for you, since we do not ahve the Flicker meter circuit, nor the time to build it and try to write the whole VI from it (at least most of us dont)
Once you add in the data aquisition part of it and are able to display a waveform, then we will probably be able to help you from there or if you cant get it working give you some hints on how to proceed the data aquisition. If you cant get the data aquisition working, please let us know what device you are using to aquire the signal, is it a digital signal or an analog signal. We will need as much information as you can give us, otherwise we are just shooting in the dark.
The best teacher is yourself, the more that you try to get it working, the more you will learn. (not to say that you cant get hints along the way

)
I know that it can seem daunting in the beginning but take it as baby steps. Get one part of the vi going, then build from there.
The vi is saved in LV 8.0
Kenny
Kenny