$G.ess variable question

Dear All, 

I am migrating from HPSM 9.30 to HPSM 9.52 

I have one question regarding boolean variables. In HPSM 9.30 we used to pu the variable $G.ess=true or $G.ess=false in format control.

However in the Process Designer, when I add the condtion Variable $G.ess Not Equals true, it shows like this from outside $G.ess~="true" (it takes it as a character true). 
How can I set this condition to be boolean ex: true  (not "true")

Thanks