Ho riprovato con un codice più ristretto l’alternativa:
`\documentclass[a4paper,oneside]{book}
\usepackage[T1]{fontenc}
\usepackage{textcomp}
\usepackage{ucs}
\usepackage[utf8x]{inputenc}
\usepackage[italian]{babel}
\usepackage{lipsum}
\usepackage[dvipsnames]{xcolor}
\usepackage{quotchap}
\renewcommand\sectfont{\sffamily\bfseries\Huge}
\definecolor{maroon}{cmyk}{0, 0.87, 0.68, 0.32}
\makeatletter
\newcommand{\capitolo}{\@ifstar{\@scapitolo}{\@capitolo}}
\newcommand{\do@sq}[1]{%
\begin{savequote}\huge\sffamily\bfseries\color{maroon}#1\end{savequote}}
\def\@capitolo#1{%
\renewcommand\chapterheadstartvskip{\vspace*{-5\baselineskip}}%
\do@sq{#1}\chapter}
\def\@scapitolo#1#2{%
\renewcommand\chapterheadstartvskip{\vspace*{3\baselineskip}}%
\do@sq{#1}\chapter*{#2}
\markboth{#2}{#2}
\addcontentsline{toc}{chapter}{#2}}
\makeatother
\usepackage{tocloft,interfaces}
\setcounter{tocdepth}{1}
\settowidth{\cftsecnumwidth}{00.00\enspace}
\makeatletter \renewcommand{\cftdot}{} \makeatother
\tocsetup{part/skip=1em}
\usepackage{titletoc}
\titlecontents*{part}[0pt]
{\scshape\color{maroon}}
{}
{}
{\vspace*{-1em}}
{}
\usepackage{hyperref}
\hypersetup{pdfborder=0,colorlinks,citecolor=black,filecolor=black,%
linkcolor=black,urlcolor=maroon,hyperindex}
\usepackage{bookmark}
\begin{document}
\frontmatter
\pdfbookmark{Indice}{Indice}
\tableofcontents
\mainmatter
\phantomsection
\addcontentsline{toc}{part}{asdaf}
\capitolo{asdaf}{prova uno uno uno}
\lipsum[1]
\cleardoublepage
\phantomsection
\addcontentsline{toc}{part}{qwerty}
\capitolo{qwerty}{prova due due due}
\lipsum[2]
\end{document}`
ma la stringa
`\tocsetup{part/skip=1em}`
non produce alcun effetto,
ammesso che sia inserita correttamente…
M.