ask at front desk and they will tell you where rest is(back of ship)and times avail.to book.
Yes, open every nite,but some open early due to pm events(ours was Vienna concert)so check.
I found food similar to what was in main dining room(just nicer presentation) and service.And NO SUBSTITUTIONS.
BUt very loud,wooden floors?,not sure.Plus menu is displayed in front and never saw it change.I didn't see it before and found out there was very little I could eat(too fancy,odd choices,etc)_but that s just me.
Some people liked it,but I d pass or check ahead of time on menu.