Hello,
NoMachine creates a hidden account, the nx user, used for internal operations of the NoMachine server only. This user, however, should not appear in the list of available users on login screen, as it’s hidden. It cannot be used to log-in to the Mac also. We cannot disable “Other Users” option in NoMachine installation process but you can do it yourself by using command in your terminal.
To disable “Other Users” option please type:
sudo defaults write /Library/Preferences/com.apple.loginwindow SHOWOTHERUSERS_MANAGED -bool FALSE
If you want to enable it back use:
sudo defaults write /Library/Preferences/com.apple.loginwindow SHOWOTHERUSERS_MANAGED -bool TRUE
However we think that ‘nx’ user on the list in “Users and Groups” preferences need more investigation and we will take a look what we can do with it.