number of items incorrect

Hi

I am still in maintenance mode as trying to solve this for client but I can give you user access if you wish.

I am making a site for a client that sells product by weight and some by units.
When a product is bought and is under 1kg for example 0.500 for 500g the items do not show up in the cart located in the menu ( despite the order / item has been added to basket).
Can you please advise me on how to reflect the number of item in cart (located in menu bar) rather than the quantities?
Thank you

The page I need help with: [log in to see the link]