Pagination and items settings in taxonomy-portfolio_entries.php

Hello,
I’ve made a duplicate of taxonomy-portfolio_entries.php for my child theme and following instructions found in other posts, modified it like this:

array(
											'linking'			=> '',
											'columns'			=> '3',
											'items'				=> '18',
											'contents'			=> 'title',
											'sort'				=> 'no',
											'paginate'			=> 'yes',
											'set_breadcrumb'	=> false,
										));

However, it is not showing 18 items.
Also, one of the images is displaying as square rather than rectangular as the others.

Any advice would be greatly appreciated.