cremecompagniet on "[Plugin: WooCommerce - excelling eCommerce] Show specific product categories and change products per page"

Hello, I have 2 questions. The first is; How do I show specific categories on a page? In woocommerce shortcodes, i found something but you have to use args, and I don't know how that works. It looks like this though:
array(
'number' => 'null',
'orderby' => 'name',
'order' => 'ASC',
'columns' => '4',
'hide_empty' => '1',
'parent' => '',
'ids' => ''
)

[product_categories number="12" parent="0"]

And my second question is, how do I change the number of products per page from 10 to 12?

http://wordpress.org/extend/plugins/woocommerce/