All Product have 30 Days Trial period After start using the product. You are permitted to register Two computers for each single user license. Users can open the ‘About’ Windows Form to get each machine's registration code. Each computer will require a unique registration code. Users must send an activation request from each machine to be registered. Users can activate the second computer for the same user and can request a replacement code due to hardware upgrades. Users must send a Request Email with 1.PayPal Account 2.Transaction Time and ID 3.Machines Registration Code to [email protected] for activation code, because the process is completely manual it may take a few day to reply the email. Note: Each version of Autodesk Revit will require a separate version of Active Code for HotGear Project Tools. Licenses are for the Revit version listed only and are independent of other versions. All licenses are non-expiring for the version purchased. Q1: This Apps is Compatible with Revit 2015 – 2017, is that only need one license key for all version? A1: All version of this App on Revit has separate Trials Days and License Code, that means you have to pay for each version if you need to use on different version of Revit. Q2: Can i request 2 different version of activation code for one license? A2:No, you have to pay for different version just like revit.