A: Hello Fabrizio

Is this offer only for new users?
>>>> Its open for all, you can use AppSumo Codes to upgrade an existing license

What do you mean by "machines," and can they be added later as addons?
>>>>
Machines is the number of devices on which you can install and activate RTILA Studio license at the same time. And yes you can increase/upgrade your license to be able to use RTILA Studio on more computers (for your team or students etc..). See our onboarding video about Machines and Licenses here: https://www.youtube.com/watch?v=aqAqUNuv6aY&list=PLiiIthEI8rAW6FTMtCros7X2w-Ian3V5m