Collection Tree - display


I would want to know two things about Collection Tree if anyone can help me.

Is it possible to display a parent collection as well as its children collection in items/show.php ? Currently, there is only a link to the children collection. I would like to have the hierarchical structure displayed.

Furthermore, I would like to display the collections only via Collection Tree, but with square thumbnails to show an insight of the items. I don’t know wich file I’m supposed to modify and how to do it.