Hello Atul Sharma,
As far as your query is concerned regarding adding a signal to an add component with different modulation scheme, yes you can do it easily. As per your system requirement you can easily use two different modulation schemes for both signals ( for one from the CW laser and one for the signal to be added in the add component). And yes you can easily change other parameters of the signals too. I hope you you would find it helpful.
Regards