The name of the file has to be exactly the same as the Name= XXXX in your render config.
These files are used by the rrClient and rrWorkstationInstaller to automatically find the render application.
The rrWorkstationInstaller uses these files to install submission plugins.
In case of the rrClient, the rrClient needs to add the application to its config.
Otherwise RR does not know which rrClient has the application installed.
You can add it manually via rrConfig, tab Per client config, sub-tab Render apps.
Or you can do it automatically via rrControl. Select the client, right click and send a "Rescan for installed software" via rrControl to the rrClient, it will automatically add the new render application.
The command is available as Command Job via the menu Clients as well (works for offline clients when they get online)