I see what went wrong there. First I clicked to install parole. And after seeing deps in "packaged to be installed", I canceled it and I unmarked parole, then selected vlc to be installed. Then saw xfce still in "packaged to be installed". Upon restarting gslapt, of course, vlc did not show xfce as a dep any more.Parole needs xfce. Vlc needs qt. That's normal.
I think there is a problem there. (not with fluxbox of course, but with gslapt).
Playing DVDs with Whaawmp got through this time all three of them, but there is still no sound. Sound is working in all other applications.
Ejecting CD - was ok this time, but then again I was not too tough on Exaile. I did not try to crash it.