Remember that owners and traders have first reservation priority at the resort, so previews are further down the list when it comes to confirmed bookings. Time of year has a lot to do with resort occupancy rates ( summer high season and other weeks where bank or school holidays bring lots of owners/traders ). Perhaps the preview quota is filling up hence the Crown Plaza serves as an alternative location. Hopefully the OP does get to stay on the resort as it's a fantastic property and they can relax the entire time on resort. But if they're consigned to the Crowne Plaza, the good news is that the resort is some 800 meters or so distant.

Playa is now a "built out" resort consisting of 5 completed buildlings. Original plans had 8 total buildings, but the global recession has put the damper on that and it is possible that Playa will remain at 5 buildings. Marriott's new strategy is wait and see for some several years to see what happens while in the mean time landscaping and developing the unused space into recreation areas. The good news is that all of the public infrastructure ( pools, restaurant, rec areas etc ) were completed 3 years ago so that the worst case scenerio for owners means less buildings/apartments, but also less people competing for the pools etc.

BTW, there's also a private restaurant at the foot of the resort on the beach as well as a couple of other nice restaurants some 200 meters up the street, so things have improved since your visit. Puerto Banus and Marbella are 5 to 8 minute drives from the resort ( Estepona is perhaps a 12-15 minute drive in the other direction ) so there's lot of shopping, dining, and a couple of casinos within easy reach of Playa.

Barry