If you want to purchase a commercial license for extra 10 PC, then follow the below steps:
1. Login into your Member's Area and access the below link.
2. You will see "Add/Renew Subscription" page, with "Membership Type" containing details about 10 PC license. Click on "Next" button located at the bottom.
3. You will be redirected to PayPal. Make the payment. You can use the same member's area login for all your 10 PCs. There is NO separate license.