First issue solved. If only the effort to solve it would have been as trivial as the issue! :-/
In the config file, the keys aren't allowed to be surrounded by quotes. So,
is OK.
The config file is read via Config::INI::Reader - a subclassable .ini-file parser, so maybe it's a no-brainer for the .ini world to avoid quotes.
But for Perl programmers... Sigh.