I too have connected through CDG more than I care to admit ... or even like ... and the most recent trip was last week when I flew BOS-CDG-FCO. Yes, you'll need to clear customs in Paris. Yes, the connection is very tight and you will most likely miss it unless one of your flights is late. Yes, your luggage will most likely not end up flying to NAP on the same flight as you. I've never arrived at my destination (when connecting through CDG) at the same time as my luggage, so when I fly Air France I now only do a carry-on. My advice is to relax because you and your luggage will get there eventually.