The license can be placed to its default location, or you have to set where to look for the license.
The default location is
<ChemAxon_home>/licenses/ folder. <ChemAxon_home> can be set by the CHEMAXON_HOME environment variable. Its default value is
<User_home>/chemaxon (on Windows) and
<User_home>/.chemaxon on Unix-like systems. <User_home> means the home folder of the user that executes the ChemAxon application.
License file can also be set by CHEMAXON_LICENSE_URL environment variable, or by the chemaxon.license.url JVM parameter.
Please note that Marvin JS license installation is different, the installation guide will be sent to you together with the license.
In order to to use license key. Plexus Connect has to be run with environment parameter -Dchemaxon.license.server.key=<LICENSE_KEY>