CRTL-Alt-F1 or CRTL-ALT-F2
Log in, and type ksmserver <enter>
You will receive something like "not installed, enter sudo apt-get install kdebase-workspace-bin"
Do it: sudo apt-get install kdebase-workspace-bin.
It will be installed.
Also do a sudo apt-get install konsole dolphin systemsettings synaptic
After this, CTRL-ALT-F7 and under KDE you will be able to install whatever necessary with synaptic.
It worked for me.
Hope this helps.
EDIT: corrected the systemsetting to systemsettings