Add more fields in frontend posting

Hi, I want to buy WCK pro because I want to add the option for users to create posts from the frontend.

This in this option: https://www.cozmoslabs.com/docs/wordpress-creation-kit-documentation/frontend-posting/#Form_Fields
As I can see, it is only allowed to add the title, the content and add the featured image.
My question is can you add more custom fields, in my case I have fields as download options, fields for iframe.
I want that to appear in the form. Is it possible to do this?

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