From OpenSCADAWiki
Q: The user operation interface starts in full-screen and I unable to close it for gain access to the system desktop environment!
Re: Of course, OpenSCADA protects the control system from closing and unprivileged access to the system desktop environment. Then, for gain access to the system desktop environment, you must be a privileged user in the user operation interface, change the interface user to your account and in the appeared global menu do needed one: disable the full-screen mode, close or quit the program. If the global menu does not appear then you have a problem of the desktop environment, such as Unity, which "tears off" the window menu; then turn off this function of the environment beforehand!