Hello Mr Vallet,
Yes Genero 2.20 is a Major Release.
But you can install it in the same directory as an existing version and add your maintenance key if you are on Unix.
Refer to the following FAQ for the installation of the maintenance key :
https://4js.com/fjs_faq/?c=37#415If you are on Windows, it is better to uninstall the old version before installing a new version in the same directory.
But do not hesitate to contact your local support center if you need any further assistance for the installation of the product.
Best regards,
Christine HEIM
Four J's Support Team