Profile: David Gimenez

Problem:

I can change authors for posts but I can't change gratuit users for my custom post type.

Solution:

Please try these:

1) Dashboard-> Toolset-> Access Control-> Custom Roles
Create a new user role, for example Gratuit2, option "Copy privileges from" choose "Author",

2) Assign those specific users to new user role Gratuit2, and test again.

Relevant Documentation:

Problem:
Hide template lyout box and astra settings for non admins

Solution:
To remove the Template Layout box for non-Admin - you should try to add the following code to your current theme's functions.php file.

add_action( 'admin_head', 'func_remove_layout_astra_metabox', 20);
function func_remove_layout_astra_metabox() {
 
global $current_user;
  
         if(!in_array('administrator',(array)$current_user->roles)){
 
         remove_meta_box( 'wpddl_template', array("student"), 'side' ); 
         remove_meta_box( 'astra_settings_meta_box', array("student"), 'side' ); 
         }
}

You can find the proposed solution, in this case, with the following reply:
https://toolset.com/es/forums/topic/hide-template-lyout-box-and-astra-settings-for-non-admins/#post-1228494

Relevant Documentation:
https://codex.wordpress.org/Function_Reference/remove_meta_box