We were on the 11 day Wonder in September and the Holiday Magic this past December. Both cruises we were bumped up to Cat 3, so I took my DDs' (8,9,11)music. Neither cruise would allow us to practice at any piano. We tried guest services, concierge and even asked Brent when we saw him walking the halls. The pianos are locked when not being played by cast members.
We were on back to back cruises january, 2005 and on the day of disembarkation/embarkation we were permitted a short period at the piano in Diversions. We were one of two cabins to do back to back. We were on the cruise11 days but they only practiced 1 day. We have a keyboard now that we will take on longer vacations. Not quite the same but it may help.