Hi Sushank,
Thanks for pointing out this bug! The BER Test Set was not generating a new random seed for each calculation. It has been fixed and will be available in OptiSystem 13.0. For now, if you need to generate a random seed each calculation, you can set the BER Test Set, to choose “external component” and connect a PRBS component to it.
As for your other questions, can you please try sending an OptiSystem project file it will help us to understand. I can’t see your attached .bmp pictures either. Can you try .png or .jpeg?
Thanks