mysterious output

[David Bobroff]

I'm having a couple of problems with the following input (I've stripped
it down to a bare minimum).

The first problem is that the  SystemStartBracket does  not appear  at
the beginning of every system of multiple staves.

The second problem is that the slashSeparator is also not appearing
except for a little bit of it at the top of the page.  Is this a problem
with software (LilyPond) or wetware (me)?

Thanks,

David

%%%%%%%%%%%% BEGIN .LY
\version "2.10.10"

gong = {
  c1
  R1*5
}

bd = {
  R1
  c1
  R1*4
}

sd = {
  R1
  c1
  c1
  c1
  c1
  c1
}

cym = {
  R1
  c1
  c1
  c1
  R1*2
}

global = {
  \repeat unfold 5 {
    s1 \break
  }
}


\score {
  <<
    \override Score.VerticalAxisGroup #'remove-first = ##t
    \set Score.skipBars = ##t
    \new StaffGroup <<
      \new RhythmicStaff <<
    \set RhythmicStaff.instrumentName = "Snare Drum "
    \set RhythmicStaff.shortInstrumentName = "SD "
    \global
    \sd
      >>
      \new RhythmicStaff <<
    \set RhythmicStaff.instrumentName = "Cymbals "
    \set RhythmicStaff.shortInstrumentName = "Cym "
    \cym
      >>
      \new RhythmicStaff <<
    \set RhythmicStaff.instrumentName = "Bass Drum "
    \set RhythmicStaff.shortInstrumentName = "BD "
    \bd
      >>
      \new RhythmicStaff <<
    \set RhythmicStaff.instrumentName = "Gong "
    \set RhythmicStaff.shortInstrumentName = "Gng "
    \gong
      >>
    >>
  >>
    \layout {
      \context  {
    \RemoveEmptyRhythmicStaffContext
      }
    }
}
\paper {
  systemSeparatorMarkup = \slashSeparator
}
%%%%%%%% END .LY