Cues and Rest Collision Warning

[Archer Endrich]

Dear Lilypond User Group,

First of all, thanks for the great discussion about variables and 
Bookpart.  I had very recently come across that problem, though in 
simpler form:  just putting a variable definition directly into a file 
that used \book (for assembling several short scores). Placing the 
definition outside \book made it all work perfectly.

I have another problem with a very simple use of cues, using code as in 
the Notation Manual.  This is my example:

%CuesandRestCollisions.ly
\version "2.22.1"

\header {
  title = "Cues and Rest Collision Warning"
}

\markup \vspace  #1

\score {

  \new Staff {
    \time 4/4
    \clef treble

    g'1^\markup{Fl 1} |
      <<
          { c'1\rest }
            \new CueVoice {
                r4^"Oboe cue" \stemUp g'8->([ a'] ~ a'2) |
          }
      >>
    r2^\markup{Fl 1} bes'8->\sfz\>([ a'] ~ a'4\!\p\<) ~ |
  }

}

\layout { }

This compiles OK but gives the warning :  cannot resolve rest 
collision:  rest direction not set

The reason I used c'1\rest was so that the rest would be placed on the 
bottom line of the Staff.  I would really like a centered rest (R1) but 
this automatically places it on the 2nd line from the top, which does 
conflict with the music of the cue.

Why does it worry about a 'rest direction' (whatever that is), 
especially when it is a breve rest.  Is there a way to avoid the warning.

Cues are minimal in this piece, so I didn't want to use a separate staff.

Finally, is it common practice to include the rest (for the instrument 
playing that part) along with the cue, which is distinguished by its 
smaller notes?

Thank you,

Archer

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CuesandRestCollisions.ly
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