Okay, so after working on this for another 6 hours I finally figured out a way to do it. It seems pretty simple now I've got it, but it's taken me until now to get my head around it. I guess that means I don't need support anymore, although I'd really like to leave this open for someone in support to have a look and let me know if there is a more efficient way of doing this. For anyone interested I have pasted in the code I cobbled together in the end..
1 – credformID is the ID number for the Cred form you are using.
3 – parent_id is the ID of the parent post this child post belongs to
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1 add_action('cred_save_data_credformID','item_title');
2 function item_title($post_id) {
3 $parentID = get_post(get_post_meta($post_id, '_wpcf_belongs_parent_id', true));
4 $parent = $parentID->post_title;
5 $post_tmp = get_post($post_id);
6 $author_id = $post_tmp->post_author;
7 $author_name = get_the_author_meta( 'display_name', $author_id );
8 $post_title="$author_name some text $parent";
9 wp_update_post(array('ID'=>$post_id, 'post_title'=>$post_title));
10 }
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Using this method gives you the post title for your post like – "'Author Name' 'your choice of text' 'Parent Post Name'"
So I could make my post title looked like "Jimmy Jim applied for the post of CEO"
Anyway, hope this helps someone else.