How can i insert an k2 extra field in News sho pro GK5?

[MorenoPla]

Hi,
I'm trying to add an k2 extra field to the News show pro GK5 module but it doesn't work.
I created the extra field and assigned it to the category of a displayed article.
In the k2 category settings, I enabled the option Extra field to Show.
In the module settings I enabled the option: Get K2 Extra Fields
Is there anything missing for to show me extra fields to the display?
I hope you can help me
Thanks
Moreno