Apologies for the confusement.

After purchase, you will be asked to sign up to our members area, of which via your username you will then have access to the downloads area where you can download content as you wish when you wish.

Due to the license discount, you can make as many games as you wish during the 2 years, and use the content commercially within the 2 years.
You can of course sell your game with arteria content in during or after the 2 years, and not have to pay any extra payments.

Steve