Lilypond and LaTeX - margins

[Beda Szukics]

Hello all

I try to print a songbook with gregorian and modern songs. For the
gregorian part I use gregorio, for the modern songs I use lilypond.

The main document is a (Lua)LaTeX-file that has text and scores in it.

My example (Versuch.lytex):

====
\documentclass[a5paper,pagesize,DIV=13,12pt]{scrbook}
\usepackage{fontspec}
\setmainfont{Cambria}
\usepackage[german]{babel}
\usepackage{gregoriotex} % for gregorio score inclusion

\begin{document}
\includescore{Gregorianum}

\lilypondfile{Tescht.ly}
\end{document}
===

with Gregorianum.gabc:

===
name:;
%%
(c3) La(h) la(i) la(h) %x10
la(i) la(h) la(i) la(h) la(i) la(h) la(i) la(h) la(i) la(h) la(i) la(h)
la(i) la(h) la(i) la(h) la(i) la(h)
===

and Tescht.ly:

===
\version "2.18.0"
\header {
  title=Tescht
}
\relative c''{
   \key g\major \time 4/4
   g4 g g g | a a a a |
   g g g g | a a a a|
   g g g g | a a a a \bar "|."
}
\addlyrics {
  La la la la lu lu lu lu
  le le le le li li li li
  lo lo lo lo lä lä lä lä
}
===

lilypond-book --pdf Versuch.lytex tells me:

lilypond-book.py: warning: Unable to auto-detect default settings:

lilypond-book.py: warning: cannot detect textwidth from LaTeX

and the song "Tescht" shows no respect for the margins :-(

So I used the package layouts.sty to determine the length of my
gregorian score lines and adapted Tescht.ly with

\paper{
line-width = 323.92374\pt
left-margin = 0\pt
}

That gave me lines of Tescht that were equal to the lines of Gregorianum
but the Tescht score is still printed about 3 mm to the left.

Why? What can I do to suppress the right margin, that lilypond is creating?

More general: Is there a way to tell the lilypond-part to adapt to the
measures of the LaTeX-file?

Greetings            Beda