Any suggestions on mode of transportation from Dubrovnik to Rome?
Fly in 80 minutes or take an 8-hour ferry from Dubrovnik to Bari and then a 4-hour high-speed train from Bari to Rome.
www.Skyscanner.com for air fares & schedules.
www.Jadrolinija.hr for ferry tickets from Dubrovnik to Bari.
www.Trenitalia.com or www.Italotreno.com for high-speed train tickets from Bari to Rome.
Any advice on Croatia Airlines?
What do you mean? They are a fine airline, I’ve flown them several times.
I've flown Croatia Air twice in 15 years and they got from A to B just fine. But I know Ryan does the route nonstop and I have flown them more often and they are actually pretty good.
I didn't check, but there used to be a night ferry I think. Still, a long and not so easy a trip for my taste when a flight is so easy.
EDIT; I went back and looked at a couple sites for ferries. If you go that way, let me know what you find.