By default, when launched, the Rumba+ Desktop Mainframe Display view connects automatically to the enterprise server associated with your project.
You need to connect Rumba+ Desktop or any third-party emulator manually to the enterprise server associated with your project.
When using the embedded Rumba+ Desktop Mainframe Display view, you can have more than one active connections at the same time, but the display is only showing one of them. To switch to a different connection:
This connects the display to the respective server and loads the application in it.
Closing the Rumba+ Desktop Mainframe Display view does not disconnect the active sessions.