Expression in flow after gateway block

Can you specify what the error you’re dealing with?

Sorry!

It looks like you haven’t properly created the variable in the instance. you’ll need to explicitly set the variable as a boolean

Haw can i do this?
It didn`t work like ${response.booleanValue == false}

Could you advise me where i can read something about using js scripts, global and local variables.
Haw can i create a variable set a value and then use it in next block.
I`m trying to use Camunda like Standalone-server and do some processing in js script. Without any Java and Node js
Is it possibly?

Sorry for my English (.