Taking data submited from ChronoForms in Joomla

Chronoforms is a good extension for building forms in Joomla.
There are good documentation in their site and is very easy to work with it.

But, how to interact with the data sent in the form build with Chronoforms ?

Here is an example.
Let's say that when we are sending an e-amil we want to make some changes if one variable has a value.
See in the picture

We know that for print a variable defined in Chronoforms we call it in this way 

{variable}

But for interact with it we do it in this way

$form->data['variableName']