Set process variable from UI Designer

Hi alll!

I am new to Bonita BPM, I am very enthusiastic about creating processes, but today I came across a problem that I have not been able to solve by searching the internet, so I go to you.

I have a process where when starting, a form has a checkbox to see if there were approved funds, if there were approved funds the process begins, if not the process ends.
Since it is not necessary to persist in the database if there were approved funds, I created a Boolean process variable "aprobado" (I'm from Uruguay, we speak spanish).

Later, in execution, I added a variable "aprobado" to use with UI Designer. The form only has a checkbox to confirm if there were approved funds, nothing more.

How do I in UI Designer to set the process variable "aprobado"?

The UI Designer variables were created automatically like this:

FormInput (JSON):
{
   "aprobado": false
}

FormOutput (Javascript expression):
return {
passed: $ data.formInput.aprobado
}

I'm using Bonita 2021.1 Build id: 7.12.1.1 

I was finally able to do it, I don't know if it's the best way but it works.

What I did was: In "data" > "Process Variable" double click on the variable, in "default value" click on "edit" and then I chose the contract entry.