The first image displays a sub-form I've created among the customized fields.
The second image displays how they look like when adding/updating an article, in the article tab Listing Info.
That is very similar to the third image:
... which is used for Listing Menus, but the difference is that Places (image 2) is added to the article tab Listing Info and the Menus (image 3) are in the article tab Listing Fields.
The third image corresponds to the xml-code beginning in Row 132 of the XML-file.
So my question is really, how can I add php-code that displays my customized sub-forms into the template e.g., listing-2.php in order to display my customized fields and FILTERING on it, without using any XML??