Custom product listing replaced with default grid when filtering products.

I'm not sure if I am missing anything, but any help is appreciated.

I've create a custom mp_productlist.php and I am including a call to mp_products_filter().

The problem I am having is that the resulting grid after using the filters does not match my custom grid layout.

Is there a place where you can edit resulting grid?

I am just getting started with learning how to theme the cart so I am not sure if I am doing something wrong.

Here is a link to my test product listing:
http://demo.desktopmasters.com/store/products/
if you use the filters, you'll see the resulting grid does not look like the initial one.