We sailed on the World Dream in January 2021, as part of a limited cruise to nowhere sailing out of Singapore. We booked a Palace Suite but had a hard time finding information on the exact benefits, so sharing our experience here.
Online check-in prior to arrival is mandatory. You receive a 15-minute timeslot to arrive at Marina Bay Cruise Centre. You are directed to the swab test area when you arrive. There is a separate queue for Palace guest, so just let the staff know and you get to skip to the front of the queue (regular queue was about 50 guests when we arrived). You get ushered into swab cubicles, get swabbed, and get a coloured number tag. You wait in the designated area for your colour, and someone will come shouting numbers, you go up to collect your test results, and you are shooed off to the main check-in.