I agree, thats what it sounds like, but im fairly sure its not...unless I'm missing something,
In the Add-software screen DVDCSS has a big green tick next to it (in both core and MD) and
apt-get install libdvdcss2 says the currently installed version is the latest, same with apt-get install libdvdread3. (again, from the director Im moving from and to)
So...can I take it from your reply that it "should" be possible?
I agree it looks like it should be installed ok... sometimes the 'Add software' screen does not tell the truth... so tis worth running it again from there. Another thing to try is run the following script from the console;
hope this helps!