Issue upgrading from 2.2 to 2.4

[Aaron Dalton]

I run Lilypond under WinXP and Cygwin.  I had typeset a number of 
William Byrd pieces under Lilypond 2.2 and have now upgraded to 2.4. 
Now my pieces don't compile.  The top of my source file is as follows:

--BEGIN TOP OF FILE--
\version "2.4.2"

\header {
        title = "Mass for Three Voices"
        composer = "William Byrd"
        piece = "Agnus Dei"
}

supMusic = \notes \relative f' {
        f2. c4 f8 \melisma  g a2 g4 \melismaEnd a2 r4
        bes4 a4. g8 f4 f~ f e d \melisma a' \melismaEnd g2 r2
        a4 bes4 c4. f,8 bes4 \melisma a4. g8 a f a4 g \melismaEnd f d e
g4. d8 f4~ f \melisma e \melismaEnd f2 r4
        f4 a c~ c8 g bes2 \melisma a8 g \melismaEnd a1~ a1
        r1 r1 r1 r1 r1 r1 r1 r1 r1 r1 r2
        a2~ a4 f a2~ a4 \melisma g8 bes a4 g8 f e4 f2 \melismaEnd e4 r2
        a2~ a4 f a4. \melisma g8 f4 g8 bes a4 g8 f \melismaEnd e4 f2
\melisma e4 \melismaEnd f2 r2 r4
        bes,4 f'4. g8 a4 bes2 a4 g2 f r4
        a2 f4 g a bes2 a4 c4. \melisma g8 bes4 \melismaEnd a2 a4.
\melisma g16 f \melismaEnd e2 r4
        f~ f e g4. d8 f4 \melisma e4. d8 d4~ d cis \melismaEnd d2 r1 r4
        a'2 g4 c4. a8 bes4 \melisma a~ a8 g f e f4 d \melismaEnd e a4. f8
g4~ g8 f f2 \melisma e8 d e2 \melismaEnd f~ f1
        \bar "|."
}
--END TOP OF FILE--

This results in the following error:
test.ly:9:17: error: unknown escaped string: `\notes':
supMusic = \notes
                  \relative f' {

*but* the file completes compiling with some semblance of readable 
output.  However, once I put the score part in...

--BEGIN \SCORE SECTION--
\score {
        \notes <<
                \context Staff = superius <<
                        \set Staff.instrument = Superius
                        \set Staff.instr = Sup
                        \set Staff.autoBeaming = ##f
                        \clef treble
                        \time 4/4
                        \key f \major
                        \context Voice = superius \supMusic
                >> %superius staff
                \context Lyrics = superius \lyricsto superius \supWords
                \context Staff = supAnalysis <<
                        \clef treble
                        \time 4/4
                        \key f \major
                        \notes \repeat unfold 53 { s1 }
                >>
                \context Staff = supAnalysisB <<
                        \clef treble
                        \time 4/4
                        \key f \major
                        \notes \repeat unfold 53 { s1 }
                >>
        >> %notes

        \layout {
                \context {
                        \Voice
                        \consists Ambitus_engraver
                }
        }
        \midi { \tempo 4 . = 120 }
} %score
--END \SCORE SECTION--

Then I get a whole bunch of the following error and nothing is generated 
at all.

test.ly:42:7: error: unknown escaped string: `\notes':
        \notes
               <<

test.ly:42:6: error: syntax error, unexpected STRING:
        \note
             s <<

I just can't seem to find any reason for this to happen.  I assume I 
have missed some major change to the way 2.4 works.  Can anybody out 
there give me a hand?

I sincerely appreciate your time and attention.
Aaron