There were even CM's getting sick! Oscar on the cruise staff complained the most. Oh, and most of our really rough days were also formal nights. It was SO FUNNY watching ladies trying to look dignified in their high shoes. I gave up on the last semi-formal night and just wore my sandals. By the end, people were getting very casual, walking around barefoot, coming to semi-formal in sweatshirts--cause yes, it WAS cold. Some even wore polo shirts for formal night--ya know, formality is good for awhile, but after a week of rough seas, ya feel a little more "piratey." Oh, and the ground moves and rooms swirl when you get off the boat. Too funny! It was just great, cuz we were all doing it together.
PS I would NEVER walk down the rock. The taxi tours are great--take you higher than the Rock Tour, as high as the cable car. We did both the Rock Tour and the Taxi tour--long story... The taxi tours will scare the heck out of you if you are WALKING down, cuz from what I heard, you have to flatten yourself against the mountain to keep from being hit by one of them.
There is an end to the Seige tunnel, so go all the way down. Take the walkway to the right that goes down in St Michael's cave--very beautiful. You won't get lost.
The BEST view you will get of the rock will be if you get up early enough to see the ship pull into Gibralter, since you only see the grassy slope when you are in port and on land, the best view is from the airport, which most tours take you to VERY briefly--you can't even get out.
I personally think the actual town was a dump, but they had great fish a chips. Oh, and you can walk from the ship to the cable cars. It's a good walk, but my five year old did it. There is a shuttle back to the ship, but we could never find it. Luckily the ship is big and not easily misplaced.
Sailing away from Gibralter, though, and rounding around the Rock, you got a GREAT view of the picturesque side, and for a long time. SO get up early and watch the sail in. Hopefully it will be light.