WordPress Category filter using checkboxes and ajax

Hi Support,
I’ve been trying to get a site that I am building to filter all posts on a page by category and sub category using checkboxes and ajax, usually I would use Search and Filter PRO for this which works perfectly however in this instance I need the parent categories to be clickable so they show and reveal the subcategories but also work as part of the filter too, I found a bit of a tutorial at this URL: http://mehimali.com.np/jquery-ajax-filtering-posts-with-checkboxes/
however when I use it on my page it basically just loads the current page into the space where the posts should be, I’ve also already spoken to Search and Filter PRO who have confirmed that what I need can’t currently be achieved through there plugin but it is in the pipeline for V3 but have no release date as yet.
Thank you
Scott Sibson