This information applies to all versions
You can activate your DxO PhotoLab software on 2 computers with the ESSENTIAL edition, and on 3 computers with the ELITE edition, as long as it is never run on more than one computer at a time. You may install it on both Mac and PC with the same license.
Please make sure that DxO PhotoLab has been removed from any computer on which it had previously been activated. If the activation doesn't succeed, please contact customer support.
To get help from DxO Support Team directly from this page, please click on this link.