sorry, not familiar with zenwalker
but, checked out their support forum page and it seems there are a few issues with vlc
how did you install vlc?
did you use 'netpkg'?
did you compile vlc? did it compile smoothly or did it complain?
you may have to compile again until there are no complaints.
your post says: 'hint: compile the qt4 plugin, and make sure it is loaded properly'
did you do that?
check the readme file that comes with vlc and any install.txt files
thats about all I can do for you