Background: I am currently in BCN in the middle of a RTW trip using my AA miles. Tomorrow I have a flight from FCO-BCN(stopover)-IST. I did not make it to Rome today like I planned because I lost my passport but I have already been issued a temporary passport.

There is no way I will make it to FCO tomorrow to catch my flight at at 7:45 am. But I can make the BCN segment because it is at noon and I am in BCN.

I already have the paper tickets. Can I just throw away my FCO-BCN segment and use the BCN-IST tomorrow or will my absence on the FCO-BCN segment cancel out the rest of my future segments?

If I cannot do this will I be able to do the date changes after I have missed my flight tomorrow morning? If I do have to make date changes I would have to do that at an AA ticket office...Is that correct? Where is the nearest AA ticket office, Madrid?