1. Fix missing shutdown
The shutdown button on the top right corner of the login in screen is missing in Deepin. You can restore this feature by installing "indicator-session" (without the quotes).
2. Delete guest session
In terminal write sudo gedit /etc/lightdm/lightdm.conf
add the line at the bottom of the open file "allow-guest=false" (without quotes)
save the file and logout and you will see "Guest session" is gone.
I posted these hoping people would find them useful.
Any ideas how to change login screen background image?