The check-in staff at the San Pedro port will be happy to scan your boarding pass to look up your records, but if you do not have the boarding pass, no big deal, they can also use your cabin number or your last name for lookup. I'm not sure about the security lines, though. On the other hand, passport books, passport cards, or birth certificates are required. Check that you have current versions with you. It is very sad to see people getting turned away because they brought expired passports or forgot them altogether.
There are only two lines at San Pedro, green lane and blue lane. No elite or suite lines. Once you check in, the elite folks (those with black medallions) get to wait in a separate elite lounge (just a slightly separate area with chairs and a few non-alcoholic drinks). Platinum level passengers have a different reserved seating area, no drinks though. Everyone else has to find seats on the other side, or just stand. This is only while waiting for boarding to start, normally around 11:00. At that point, elites get to board first, then platinum, then those of us in the teaming masses. That all clears out in about 15-30 minutes, then everyone who arrives after that can board at their leisure.