To make the changes to the file, you will need to have local access to the server that the TIBCO.Nimbus server is installed on. You will then need to navigate to the following path within the Nimbus installation: \Web Server\App\Localisations . In this folder you will see a list of files called "localisations" and then the extension that relates to the specific translation file. For example, the German file would be called "Localisations.de" and the Japanese file would be "Localisations.jap". You will need to find the file that relates to the changes you want. Once the changes have been made and saved you will need to restart the web server.
Note that if you are currently hosted on the TIBCO.Nimbus cloud service that you will need to raise a service request so that we can make the relevant changes as you will not be able to navigate to the folder that stores this information.