Hi Prepu,
Invoice King Pro wasn’t really intended for ecommerce use however there has been a few requests for intergrations with other systems and plugins. I do plan on building these intergrations as addon installs to the base plugin, unfortunately I’m fighting with time between my full time work as well as freelance work to be able to work on my own projects.
As soon as there is something available for this, I will notify you here.
[EDIT] Not to shoot myself in the foot here but it seems there is an intergration for WooCommerce for what your after already.
https://www.woothemes.com/products/pdf-invoices/
As mentioned, Invoice King Pro isn’t really built for this use. If something were to be built along the lines of what your after, it would be an addon and would be charged for.