Hi Tarun Nayyar,
Can you please share your entities so that I can compare it with mine. I am getting a false on Reload but you mentioned that you are receiving a null.
I guess,i didn't explain it well.
I ran your entities.It gives "false" everytime 1st mashup loads. But as per requirement,it should give false only for the first time and once user changed the state of checkbox to true,that "true" should get persisted and on next visit same mashup should get "true" from session variable,which is not the case.
So, we actually need to uncheck the Persistent property so that the value resets on each login.
Also, we need to update the Session Property only when the checkbox changes.
Make the Boolean property non-persistent and try with following entities.
I hope it helps.