The dress code for the MDR is basically for dinner, you can wear shorts and swim wear with a cover up for breakfast and lunch.
I don't ever recall the Windjammer open 24/7...Princess has the Horizon Ct. that is open all the time.
I believe there is a small charge for room service after a certain time, late at night, but otherwise, just a tip would be nice to give the person who delivers your order.
Yes, both Chops and Portofino's have the extra charge, have eaten at Chops and I thought it was well worth the extra bucks. Also J. Rockets is an extra charge..
I recently read about bringing 2 bottles of wine onboard, that may be per person?? Something you may want to check into further, to see if you can bring 2 more..