Hello PabloW3V, what’s your question? How to use the shortcode and set the widget options which is placed by shortcode? So you can read this: http://tiptoppress.com/use-shortcode-to-add-category-posts-widget-to-the-content/
The question is how to use two or more categories? We support multi category selection only in our premium widget. Our premium widget has many more options, multi selection for categories is one: http://tiptoppress.com/term-and-category-based-posts-widget/
Another tip is: You can try the new 4.7 beta 1 code which supports till this beta 1 multi shortcode widget instances. So you can try set many widgets above and choose different categories, like a category split layout.
Downlaod Category Post Widget 4.7 beta 1: https://github.com/tiptoppress/category-posts-widget/releases
Blog post for using multi shortcode: http://tiptoppress.com/new-4-7-multiple-shortcodes/
I put the shortcode and I went to the customize page but didn’t show the item “Category Posts Shortcode”. I tried in the preview version and the publishing version but it didn’t change.
Do you know something that i can do or it is a “conflict” with the theme?
Customize page Image (Google+)
Make a Theme test you can change your Theme and use one which is delivered with WordPress like TwentySixteen, TwentyFifteen
I tried out, but it works for me: You have to save the site or post and also after adding the shortcode click save.
But for me “Drafts” work and without saving I have no page to show or if I don’t save I can’t change to customizer.
Is the widget works added to the widget area as normal widget? I mean, have you activated the widget in the admin panel: PlugIns > Installed PlugIns
If you use a free Theme can you give us the name of the used Theme?