yes, the task bar show all windows is fixed
Code:
for LXDECONFIG in "$HOME/.config/lxsession/LXDE/config" "$HOME/.config/lxsession/LXDE/desktop.conf"; do
 [ -r "$LXDECONFIG" ] || continue
 # X2Go: Can't use compiz
 if [ -n "$X2GO_SESSION" ]; then
  if grep -q '^window_manager *= *compiz' "$LXDECONFIG" 2>/dev/null; then 
    sed -i -e 's|^window_manager *= *compiz.*|window_manager=openbox-lxde|g' "$LXDECONFIG"
  fi
 else
  if grep -q -v '^window_manager *= *compiz' "$LXDECONFIG" 2>/dev/null; then
   sed -i -e 's|^window_manager *=.*|window_manager=openbox --replace|g' "$LXDECONFIG"
  fi
 fi
done
I'm not sure if that
window_manager=openbox --replace
(it was originally compiz --replace)
should actually be
window_manager=openbox-lxde

anyway, it works without any discovered flaws