I'll be transiting through FCO on a sunday morning in october, from dubrovnik on croatia airlines, connecting to detroit on delta, all on the same KLM PNR. The connection time is only 45 minutes, from what I've gathered so far that is pretty optimistic on the airlines part. I assume I'll have to go through another security check, will there also a passport check? I've never been to FCO, any particular pointers?

Not real concerned if I miss it, it's the return trip home and I've never been to rome.