I just go to KDE, Internet, Desktop Sharing on the core, and use any VNC program on my laptop. It always connects with no issues and is actually a very smooth responsive connection. The only downside I see is that from the core you have to accept the connection, then you have to put the password that the core gives you into your other pc. Not a huge deal, but it means that I have to sit in my closet and have a monitor hooked up to my core to get the connection established.
I am sure there is some setting that lets you just dial in remotely (without having to accept or use a password), but I havent messed with it yet to find out.