Slur through a rest

[Jonathan Wilkes]

Hello,
     Below is an example of a slur that's stumping me.  Could anyone 
suggest a way of avoiding the rest that doesn't mess up the continuation 
after the line break?  I've tried adjusting 'positions but it doesn't 
produce an effect.

Also, I noticed that when I use the \break that is commented out instead of the 
other one, I get the following error and no line break:

warning: forced break was overridden by some other event, should you be using 
bar checks?

It obviously has to do with grace notes, and I saw a relevant email here:

http://lists.gnu.org/archive/html/bug-lilypond/2005-10/msg00040.html

but what does it mean to "sync" grace notes across staves?

Thanks,
Jonathan

snippet:

\version "2.13.3"

staffPiano = \new PianoStaff {
        \set PianoStaff.midiInstrument = #"acoustic grand"
        \set PianoStaff.instrumentName = #"Piano  "
                \time 3/4
                                <<
                \context Staff = "RH" {  % Right hand 
                        \clef treble
                        \key c \major
                        \relative c' {
                                \new TimeSig    
                                  R2. | R2. | r4 r s4 | s2. %\break
                                  |
                                  s2. | R2. | R2. |
                        }
                }
                \context Staff = "LH" {  % Left hand                    
                        \clef bass
                        \key c \major
                        \relative c {
                                <<
                                { s2. | 
                                  s2. |
                                  aes8^\p\( bes \times 2/3 { f' g d' } \change 
Staff = "RH" fis b |
                                  e bes' \times 2/3 { c g d } \times 2/3 { 
fis'4-- e,8 } \break
                                  |
                                  \grace { aes16[ bes] } g'4~--
                                  \times 2/3 { g8 e \acciaccatura a, <des, a'> }
                                  <des a'>32 c'8\) r16. | \change Staff = "LH" 
s2. | s2. |
                                }
                                \new Voice { R2. | R2. | s2. | R2. | R2. | 
R2.*2 }
                                >>
                        }
                }
        >>
}

\score {
        <<
                \staffPiano
        >>
}