InstallDir = /usr/local/me

....

cfgFile = [InstallDir]/conf/me.cfg

##</code><code>##

cfgFile = [ConfigDir]me.cfg
...

my $cfg = "me.cfg";
my $configDir = "/usr/local/me/conf/"; # Unix/Linux
#my $configDir = "C:\\Program Files\\me\\conf\\"; # Win32
my $vars = new ModuleName($cfg, ConfigDir => $configDir);