For the DVD playback issue (getting the error even after "libdvdcss2" is installed), oddly enough, installing "libxine1-ffmpeg" from Adept did resolve the issue. So, if you're having the error, give it a try.
For the DVD playback issue (getting the error even after "libdvdcss2" is installed), oddly enough, installing "libxine1-ffmpeg" from Adept did resolve the issue. So, if you're having the error, give it a try.