<eu> environment causing problem with index

[smpklimach]

We wanted to make an alphabetical index of all antiphones at the end of our liturgical book. But we stumbled upon the following problem:
The layout gets totally messed up, if there is any <eu> environment in the scores. It doesn't cause problems if the index is one-columned and the problem in the 2-columned version disappears as soon as we delete all <eu>-tags. But neither is an option.
Any idea how to fix this?

Example files:

beatiquipersecutionem.gabc:

name: beati qui persecutionem;
office-part: laudes;
occasion: commune apostolorum;
date: ;
transcriber: Kloster Helfta;
transcription-date: 2013;
style: modern;
annotation: {\textcolor{red}{Ant.}};
annotation: viij. T.;
commentary: Mt 5,10 ;

%%

\textcolor{red}{B}e(c4h)á(fg)ti,(g) \textcolor{red}{*}()
qui(f) per(h)se(g)cu(j)ti(i)ó(hjg)nem(g) pa(g)ti(g)ún(fe)tur(f) (,) prop(d)ter(e) iu(f)stí(gh)ti(h)am.(g)
(::) E(j) u(j) o(i) u(j) a(h) e.(g) (::)

Tex-file:
\documentclass[fontsize=13pt,twoside]{scrreprt}
\usepackage{graphicx}
\usepackage[paperwidth=155mm, paperheight=220mm]{geometry}
\usepackage{gregoriotex}
\usepackage{color}
\usepackage{parallel}
\usepackage[latin, german,francais]{babel}
\usepackage[utf8]{luainputenc}
\usepackage{fancyhdr}
\usepackage{verse}
\usepackage{imakeidx}

\makeindex[columns=2]

\begin{document}

\index{Beati qui persecutionem}
\index{Test Nr. 2}
\gregorioscore[a]{beatiquipersecutionem}
\index{Noch eins}

\printindex

\end{document}

[rpspringuel]

I think your problem doesn't have anything to do with the <eu> tags, but rather with some of your other constructions that are less than idiomatic. Try the following:

gab file:

name: beati qui persecutionem;
office-part: laudes;
occasion: commune apostolorum;
date: ;
transcriber: Kloster Helfta;
transcription-date: 2013;
style: modern;
annotation: {\textcolor{red}{Ant.}};
annotation: viij. T.;
commentary: Mt 5,10 ;

%%

Be(c4h)á(fg)ti,(g) *()
qui(f) per(h)se(g)cu(j)ti(i)ó(hjg)nem(g) pa(g)ti(g)ún(fe)tur(f) (,) prop(d)ter(e) iu(f)stí(gh)ti(h)am.(g)
(::) <eu>E(j) u(j) o(i) u(j) a(h) e.</eu>(g) (::)

TeX file:

\documentclass[fontsize=13pt,twoside]{scrreprt}
\usepackage{graphicx}
\usepackage[paperwidth=155mm, paperheight=220mm]{geometry}
\usepackage{gregoriotex}
\usepackage{color}
\usepackage{parallel}
\usepackage[latin, german,francais]{babel}
\usepackage[utf8]{luainputenc}
\usepackage{fancyhdr}
\usepackage{verse}
\usepackage{imakeidx}

\makeindex[columns=2]

\let\GreStarold\GreStar
\def\GreStar{{\textcolor{red}\GreStarold}}
\grechangestyle{initial}
  {\begingroup\fontsize{40}{40}\selectfont\color{red}}%
  [\endgroup]%


\begin{document}

\index{Beati qui persecutionem}
\index{Test Nr. 2}
\gregorioscore[a]{beatiquipersecutionem}
\index{Noch eins}

\printindex

\end{document}

[smpklimach]

Thank you for your answer and the hint about the far more elegant way to get initial and star coloured. But unfortunately it doesn't change the look of the index at all. Even with your new files - with eu tags the 2-columned index looks horrible, without the eu-environment the index seems to be fine.

[rpspringuel]

I get the same results for the index regardless of the presence or absence of the <eu> tags using the files I provided. If you're getting something different, then I'm going to need more information about your setup.

[smpklimach]

What kind of information do you need?
I use Gregorio 5.1.1 (kpathsea version 6.3.0) and TeX Live 2018. My OS is Solus, but on another computer with Ubuntu we had the same issue.

[rpspringuel]

I recommend updating to TeX Live 2021 and Gregorio 6.0.

_{Sent with GitHawk}

[smpklimach]

This did indeed solve the problem with the index, but now I have the problem with the superscript numbers (#1537) on this computer as well. With the old version of TexLive and Gregorio the superscript numbers were shown, with the new versions I get error messages and the commentary is not printed out at all.
So now I can print my book either with superscript numbers or with a nice index...