Cheapest way to get from Verona to Carconne, and Carconne to Lucerne?

I'm travelling with a partner through Italy: we're starting in Naples, going to Rome, then Verona. From Verona we need to get to Carconne, France. After our stay there, we're headed from Carconne to Lucerne, Switzerland. What's the best way to do this? We've looked at rail pes and options extensively, but would like some advice from people who have done this before, as we have never been to Italy or southern France before. Thanks for any help!!