Removal of Billing Process in Checkout Process

I want to remove the billing process in checkout process . I am building an application of download-able products so I dont need the billing process and shipping process.I have disabled the shipping via adding download-able product .So its working fine .Now I also want to remove the billing step from the checkout process.

I had tried  so many things but nothing had helped me yet.....
I found a link
https://www.nopcommerce.com/boards/t/5200/can-i-remove-the-billing-address-step-from-the-wizard.aspx
But it also didnt work for me .....Please suggest me some solution as soon as possible.....

Thanks in advance........

You have to change the logic in the program and rebuild.
There are other posts about this sort of stuff.
A