We use the Umbrella spotter. Getting out of the water at the family beach or coming back from the potty and being able to find our things is great. They have a no saving policy at the pools but not a Castaway.
Not sure what ship you are on, but here is a pic of the desk and outlets on the Fantasy and Dream.
http://photopost.wdwinfo.com/showphoto.php/photo/61773/title/deluxe-oceanview-with/cat/1220
here is a pic of the Magic, I would think the Wonder would be similar...
Head to the tall yellow building. this is where you can get your passport stamped.
https://www.google.com/maps/search/port+of+nassau,+nassau+bahamas/@25.080721,-77.3411,3a,75y,90t/data=!3m8!1e2!3m5!1s3630257!2e1!3e10!7i2048!8i1536!4b1
It is actually 60 days in advance. See the first paragraph.
http://dcl.wdpromedia.com/media/dcl_v0400/Site/PlanningCenter/Media/SpecialServicesInfoForm-June-1-2015.pdf