HFM Manage Taskflow - use variables

Hi gurus,

in HFM 11.1.2.0 I want to create a dynamic task flow "Administration -> Manage Taskflow" to consolidate periodically scenarios and periods.

I saw there is a button "variables" but it is never active, how can I create and use a variable in my taskflow steps?

Is it possible to use only exit variables of task flow steps?

If it is not possible to use variable, how can I avoid to enter every time in the taskflow step to change the PoV?

Thanks in advance!