This seems to work great, thank you!

#use DateTime::Util::Calc qw(mod);
#sub mod { $_[1]*1 ? $_[0] % $_[1] : 0);}

sub mod {
   my($x)=$_[0];
   my($y)=$_[1];
   while($x >= 0){
      $x-=$y;
   }
   $x+=$y;
   return($x);
}
[download]