Installer can be closed
The OS installer can be closed, and cannot be opened again. There is probably a way to do this using the TTY (provided you know the password), but not from the desktop, as it is locked. Since I do not know much about this project, I am unsure whether this will eventually be useable in production, or will always be for testing. If it's only really for testing, this is probably not much of an issue.
Edited by TheKodeToad