IT GOES BEAUTIFULLY except with many hitches along the way because Fai is determined to spike the punch even though everyone's legal (idk there are small children FROM SOMEWHERE in attendance who should not be consuming alcohol) and he keeps trying to get Syaoran to go into Sakura's room before the wedding EVEN THOUGH EVERYONE KNOWS IT'S BAD LUCK and of course, right before the ceremony, Mokona does something horribly offensive to Kurogane, and the ceremony is delayed by half an hour as the guests try and restrain angry Kuro-papa.
BUT. The bride looks stunning, the groom is about to fall over in joy, everything goes smoothly after the ceremony actually starts, and by the end of it all the guests are sobbing into their handkerchiefs. The band playing at the reception plays all the right songs, the food is delicious, and overall the event is absolutely wondrous.
...I don't think I quite answered your question properly but um... that's how it goes? 8D;