Newbie Questions

[rickythesk8r]

I'm a new user of Lilypond. After some experimentation, I've encountered 
a couple of situations where I suspect that I am not using the program 
correctly.

1. In the second alternative to the repeat, the \repeatTie's are 
concave. I tried tweaking with ^ but it does not seem to have the 
desired effect.

2. The whole rest in the last measure is not centered, which, I believe, 
is the conventional location (in organ music, at least).

3. A warning.

        can't end volta spanner
        [5],

   is issued, apparently because the length is tweaked to end at the 
double bar in the second alternative. It appears to be necessary to 
include an extra measure in the second alternative in order to tie the 
new voice across the bar.

One further effect I'd like to achieve is to mimic the labels of the 
volta spanners that appear in the text I am working from: "1ma" and 
"2nda", where the "ma" and "nda" are raised above the line with a "dot" 
beneath.

Thanks in advance for your help.

\version "2.10.25"

soprano = \relative c'' {
  \repeat volta 2 {
    c16[ e c e ] d[ f d f ] \voiceOne b,[ g a b ] c4~
  }
  \alternative {
    { c b c r }
    { c^\repeatTie b c2~ \bar "||" |  c r8 c[ c c ] }
  }
  e4 r8 d c[ c ] c[ b16 c ]
}

alto = \relative c' {
  \repeat volta 2 {
    s2 \stemDown d4
    <<
      { \voiceThree g~ }
      \new Voice {
        \voiceTwo r16 e[ d c ]
        \oneVoice
      }
    >>
  }
  \alternative {
    {
      <<
        { g'4. f8 g4 \voiceTwo r }
        \new Voice {
          \voiceTwo d2 e4 s4
          \oneVoice
        }
      >>
    }
    {
      <<
        { \voiceThree g4.^\repeatTie f8 g2~ | g2 \voiceTwo r }
        \new Voice {
          \voiceTwo d2 e2~ | e s
          \oneVoice
        }
      >>
    }
  }
  r1
}

<<
  \new Staff {
    \set Staff.voltaSpannerDuration = #(ly:make-moment 4 4)
    <<
      \soprano
      \alto
    >>
  }
>>