Alessandro,
I made a script with snippets from some of our tutorials, mainly the tutorial on exporting to Excel. With the script I have a variable called numChannels, which you can modify to be any integer value. The script then generates and modifies components to create a layout like the 20 channel example attached. It then runs the simulation and saves the results from the BER Analyzers into Excel, which can then be used to plot the BER as a function of frequency. I will let you change the frequency to wavelength 
With this example and an understanding of VB Scripting you should be well on your way to solving your particular problem. Hope it helps!