usepackage{forarray}
usepackage{xstring}
newcommand{getIndex}[2]{
ForEach{,}{IfEq{#1}{thislevelitem}.  {numberthislevelcountExitForEach}{}}{#2}
 }

setcounter{secnumdepth}{0}

newcommand{getAff}[1]{
getIndex{#1}{$for(address)$$address.code$$sep$,$endfor$}
 }

$for(author)$
$author.name$textsuperscript{$for(author.affiliation)$getAff{$author.affiliation$}$sep$,$endfor$}$if(author.corresponding)$textsuperscript{*}$endif$$sep$,
$endfor$
\
bigskip
$for(address)$
textbf{getAff{$address.code$}}$address.address$\
$endfor$
bigskip
$for(author)$
$if(author.corresponding)$
* Corresponding author: $author.email$\
$endif$
$endfor$