[path]
files=foo.txt,bar.txt,baz.csv

##</code><code>##

@files = split /\s*,\s*/, $config->{path}{files};
 # the \s* removes the optional whitespace around delimiters

##</code><code>##

foreach my $Section (values %$config) {
 # $Section is a hash ref containing the values of the section, not the section name!
  foreach my $value (qw(files colors and other options that should be arrays)) {
    $Section->{$value} = [split /\s*,\s*/, $Section->{$value}];
  }
}